6.2 suddenly smoking bad after cold start ,and misfiring..

[diesel4me]

I think your electric pump shit the bed too...

Winner Winner--Chicken Dinner..

Rene nailed it...looked at the electric pump yesterday afternoon,had to lay in a deep puddle,sure enough,one of the wires going into the "can" was melted and the rubber bootie seal around it was fried,like it had started to burn..

No one locally has a universal electric pump in stock either,every place says "we can get one tomorrow--but you'll have to pay up front for it"..so that means TWO rides I'll have to bum to go get one-.

-I have three bills to pay today too,I may have to just risk driving it with the pump "dead" and pray the lift pump on the engine will be enough to get me around town at lower speeds..heavy rain is moving in too,its 55 degrees here with winds gusting almost as high as the temperature..wont be a good day to get stranded..

 

[tRustyK5]

On the upside that isn't a terribly expensive or difficult repair.

 

[K5wrench]

The smoke on cold start does not fit with a bad lift pump.

As for the lift pump; it would be a good idea to replace the mechanical pump and eliminate the electric pump.

If the mechanical pump fails in such a way as it leaks diesel, it is possible for the electric pump to fill the crank case with diesel.

Really, the stock lift pump is perfectly adequate.

 

[diesel4me]

The smoke on start up I think is either dead glow plugs in a few cylinders--or perhaps a few cylinders are losing compression..could be the injectors ,they have never been touched..but as long as it runs OK warmed up I'm not going to go looking for more troubles..


Yeah,I knew that could happen (the electric pump filling the crankcase if the lift pump diaphragm fails),but having the electric pump in tandem makes bleeding the system so much easier,and the engine seems to start faster and run peppier with it too..

Also if the lift pump fails,it still can fill the crankcase with fuel too...and its such a sucky location its mounted in,I don't feel I could be successful at replacing it..

Frankly I'd rather yank the engine out and leave it out if it needed a lift pump..its just one more nail in its coffin....it has enough other potential failures waiting to happen I just assume stop throwing money at it..as it stands now it needs at least a few glow plugs,the oil pan replaced,the passenger side exhaust manifold is ready to crumble,and it is noisy enough to make me think it is nearing its end ,period..

In the past when I changed the fuel filter or stupidly ran it out of diesel,all I had to do was open the bleeder on the filter,turn the key on,and the electric pump would fill the lines and filter,and I didn't end up cranking it so long that the batteries died,or the starter burnt up..

I roached 2 starters and the batteries after running it out of fuel twice in the past 10 years..that alone doesn't exactly make me fond of diesels..nothing on this engine is "inexpensive" either..

I've looked locally for another electric fuel pump--all the usual stores like Autozone,Pep-Boys,Advanced Auto,all stock either Mr.Gasket or Holley pumps that look identical,and they SUCK,I've seen at least a half dozen of them friends bought fail either right away,or shortly after installing them--they have to be "gravity fed",they aren't self priming,and they sell for over $50--screw that junk..

Online you can find hundreds of different pumps starting under $10 from Amazon,E-bay,but their reviews are full of "don't buy these--they are junk" posts...

I had one brand new pump identical to the one on my truck I bought for $1 at the flea market,still in the package,I bought it for a "spare",but ended up using it on a garden tractor instead--it worked great all that summer--6 months later I went to use the tractor and the pump started smoking as soon as I turned it on,and then it croaked..
I did an autopsy on it,inside of it looked like roofing tar,the gas turned the rubber bellows into goo..

So I'm not a big fan of the "fuel filter" looking electric pumps or the Mr.Gasket style junk--if I buy one ,it'll be the "cube" design like a Facet brand,with a plunger instead of a bellows diaphragm type..

Funny the one on my truck when I got it lasted 16 years and roughly 10,000 miles though..I think diesel is less destructive to the innards than ethanol gas is..

It is a bit un-nerving to think these pumps could fail and start the fuel on fire--this one didn't even pop the 5 amp fuse,but the ground wire on it melted and came right out of the case when I touched it..
There are integrated circuits,resistors and capacitors inside the pump too,probably submerged in the fuel..

For now I may just by-pass the electric one with a hunk of brake tubing,put it back to stock,and pray the lift pump doesn't croak next..

I'm not feeling great and I'll be lucky to get that done,I'm feeling like a 80 year old cripple lately..--it will be a hassle to get a credit card so I could order anything online,it is bad enough I have to blow at least $40 on glow plugs when I'm dam near broke from paying my property taxes and utility bills....
I also now have to get two more tires that "match" two on the truck,
I had some scary drive line "BANGS" plowing with the mis-matched ones on it now,was lucky I didn't break something ..more $$$ I don't really have to spend on this p-o-s..

 

[diesel4me]

Managed to test the glow plugs yesterday,using the test light method,all on the drivers side tested OK,and that is the bank that all the white smoke belches from after a cold start for several minutes--so I guess its either a compression issue in one cylinder or maybe an injector is dumping too much fuel,no knocking noises though,but it does "skip" and run lopey till it warms up..coolant level is full,no bubbling or anti-freeze smell from the exhaust,it is fuel for sure..

Once its fully warmed up there is no excssive smoking and it runs about the same as it ever did..

The passenger side bank has one glow plug that's been unable to be removed since I got it--all the others tested good ,except the rear most one,that I couldn't reach to test,I assume its good if the other 6 were..

I see the exhaust manifold on that side has a piece of it that flaked off,leaving a slot shaped hole around the mid section of it....

When you start it cold you can see puffs of smoke blow out of it--it isn't noisy yet,but it wont be long now..and it is so thin,welding or brazing it will only result in a bigger hole being made..tried that on the drivers side when it did the same 2-3 years ago, and only made a huge hole..
The exhaust leak was blowing right on one of the injector return line rubber hoses....so I couldn't trust driving it that way..it took me three days to get the old manifold off in pieces and extract all the bolts I had to cut off..

That job took 10 years off my life span,and I'm not even going to attempt to do the other one myself with the engine in the truck--if I didn't luck out and have a pair of good used exhaust manifolds I got for free off a 6.2 I picked up for parts with a busted crank,the engine would have been yanked out and probably scrapped back then..(wishing now I had,seeing I probably cant do it now)..

If I had to buy exhaust manifolds,I'd be lucky if new ones exist at all,and I saw used ones on E-bay listed for $400...that's insane,for an engine that might have cracked main bearing webs or a crank tha'ts about to fail..another good reason to ditch the 6.2..
I don't even feel its worth the effort or expense to replace the manifold..it may get some "Pyro-Putty" put on it and the hell with fixing it "right"..

I took the hoses off the dead electric fuel pump and spliced them together with copper tubing ,so the fuel flow wont be restricted and now I may be able to drive at normal highway speeds and pull hills without it bogging out and stalling..
I left the pump in place,it was freezing out and getting dark by the time I got the hoses spliced,so I haven't done an autopsy on it yet..

Just doing these simple tasks has my chest aching like I got kicked in the ribs the past 2 days,and every muscle in my body feels sore and bruised..I'm afraid I'm going to have to end up in a hospital if this keeps up,and find out why I feel like I'm dying every day..

 

[diesel4me]

Well,had to go pay Verizon today and get some food,and the frigging 6.2 still wants to die if I stuff my foot in it to get it up over 45 mph..
So evidently the dead electric pump wasn't causing a restriction like I assumed..

So,I guess I now get to blow another $26 on a "special order" fuel filter no one stocks locally,and see if that cures it--I'm not looking forward to getting the dam thing started after replacing the filter--last time even after I filled it before installing it ,it started right up,then died,and I had to recharge the batteries to get it to crank long enough to finally get it to fire up again...

The filter was replaced about 2 years ago,only has maybe 3000 miles on it..
I know all it takes is one bad tank of fuel to clog one,but I kind of doubt it is plugging up...and if the fuel had water,I'd think it would not start so easily..nor would it run good even after its warmed up..

I don't know what else could be causing this,it wasn't cold enough to cause the fuel to gel today....the lift pump seems OK,it starts up almost instantly cold,and I know there is no air getting in the fuel lines.....

 

[tRustyK5]

I had a filter clog up on my 83 when were moving to Alberta. Really down on power, surging, running like shit. I was so happy we made it to the nearest larger town. I just bought a few things at the auto parts place and bypassed the filter entirely.

it ran super good after that. haha. I always meant to fix it right when I got here, but never did.

 

[diesel4me]

I carry a big metal gas filter with me in the truck,that I had 2 of,from a VW of all things,it is about 4" in diameter and as long,with 9MM fuel barbs..holds about a pint of fuel..

I kept it in the truck in case I had a plugged filter again (last time 2-3 years ago,I had to pay a friend $100 to tow my truck home from where it died 15 miles away and had to be left overnight in a business parking lot--was lucky no one molested it ,I got the owners permission--any other tow company would have charged at least $150)....

I might have been able to fudge that spare filter on it and gotten home,if I hadn't killed the batteries trying to get it to start and off the busy 2 lane highway..

I should have got two fuel filters back when I put the new one on--a friend worked at a big rig truck supply company and he got me a Baldwin BF781 for his cost around $18,he even brought it to my house..don't know if he still works there,I used to work with him at one of the parts stores,and he doesn't come to visit me,lives in another town now..

I hate paying so much for a stupid fuel filter..one for a gas engine ,I have several of "in stock" and can buy them anywhere for under $5..

Things like this are what irritates me about a 6.2..everything costs quadruple,even the motor oil,and glow plugs,starters,and everything I go to repair on it is difficult --doing a lift pump or a water pump would finish me off,and if either of those need replacing,I'm going to give up and take it off the road,maybe yank the f-n thing out and sell it to someone who thinks diesels are cool,if my physical condition improves..I certainly don't now--I did at first,now 16 years later I'd never own another one ,except maybe a VW TDI..

I was tempted to buy a remote oil filter base I saw for $5 at a swap meet and use a regular oil filter for a fuel filter,but I wasn't sure if they would work on diesel fuel instead of oil,their micron ratings aren't any worse than the "right" filter--but they have no bleeder vent,but you could add one easily--no drain valve either,on an oil filter..but an oil filter can be had anywhere for $5..why they get so much for a diesel fuel filter that is basically the same thing only with a drain valve, is a ripoff ..plus no one here HAS one on the shelf..

Maybe I could go with the larger "can" big rig filter number that will fit the spin on base--perhaps those are more common and might be in stock locally--and cheaper,seeing fleets use a lot of them..

I also thought about using one of the several oil furnace canister type filter setups I have,but those suck to change out,they use a filter that looks like a ball of string,and are the same 10 micron rating,and have a bleeder vent but no drain..

We're going to have another sub-zero cold stretch headed here later this week..might get a little snow,rain,and back to snow first,and I still need to find two "matching" tires if I want to use 4WD to plow,and I'm not looking forward to the cold,I know the 6.2 will be a pain in the butt to get started,and I don't even want to drive it anywhere running the way it is..

 

[imiceman44]

I carry a big metal gas filter with me in the truck,that I had 2 of,from a VW of all things,it is about 4" in diameter and as long,with 9MM fuel barbs..holds about a pint of fuel..

I kept it in the truck in case I had a plugged filter again (last time 2-3 years ago,I had to pay a friend $100 to tow my truck home from where it died 15 miles away and had to be left overnight in a business parking lot--was lucky no one molested it ,I got the owners permission--any other tow company would have charged at least $150)....

I might have been able to fudge that spare filter on it and gotten home,if I hadn't killed the batteries trying to get it to start and off the busy 2 lane highway..

I should have got two fuel filters back when I put the new one on--a friend worked at a big rig truck supply company and he got me a Baldwin BF781 for his cost around $18,he even brought it to my house..don't know if he still works there,I used to work with him at one of the parts stores,and he doesn't come to visit me,lives in another town now..

I hate paying so much for a stupid fuel filter..one for a gas engine ,I have several of "in stock" and can buy them anywhere for under $5..

Things like this are what irritates me about a 6.2..everything costs quadruple,even the motor oil,and glow plugs,starters,and everything I go to repair on it is difficult --doing a lift pump or a water pump would finish me off,and if either of those need replacing,I'm going to give up and take it off the road,maybe yank the f-n thing out and sell it to someone who thinks diesels are cool,if my physical condition improves..I certainly don't now--I did at first,now 16 years later I'd never own another one ,except maybe a VW TDI..

I was tempted to buy a remote oil filter base I saw for $5 at a swap meet and use a regular oil filter for a fuel filter,but I wasn't sure if they would work on diesel fuel instead of oil,their micron ratings aren't any worse than the "right" filter--but they have no bleeder vent,but you could add one easily--no drain valve either,on an oil filter..but an oil filter can be had anywhere for $5..why they get so much for a diesel fuel filter that is basically the same thing only with a drain valve, is a ripoff ..plus no one here HAS one on the shelf..

Maybe I could go with the larger "can" big rig filter number that will fit the spin on base--perhaps those are more common and might be in stock locally--and cheaper,seeing fleets use a lot of them..

I also thought about using one of the several oil furnace canister type filter setups I have,but those suck to change out,they use a filter that looks like a ball of string,and are the same 10 micron rating,and have a bleeder vent but no drain..

We're going to have another sub-zero cold stretch headed here later this week..might get a little snow,rain,and back to snow first,and I still need to find two "matching" tires if I want to use 4WD to plow,and I'm not looking forward to the cold,I know the 6.2 will be a pain in the butt to get started,and I don't even want to drive it anywhere running the way it is..

The big rig filters are more expensive, $20 for the cheap ones.

 

[diesel4me]

That's cheaper than most of the stores here get for the "stock" Wix 33123 water separator filters.....

May as well go with a Wix 33418 or whatever brand crosses to that number then--the only difference is the 33418 is about 2" longer,both have the same gasket base dimensions and are 12 micron rating..

I discovered in my searches those home furnace oil canister filters are used on some Detroit Diesel industrial engines on equipment!..and they are a 10 micron rating..

I can get replacement cartridges for those at any Home Depot or Lowe's for about $5...I'm tempted to swap one of those on the truck,but probably wont--for one thing those dont have a water drain and probably aren't a "water separator",just a filter.. plus its too dam cold to be outside fiddling around ,I just want the dam thing to run right before it really gets frigid later this week..

 

[diesel4me]

Well,an update,no real good news..

Truck sat during the extreme cold 3 days last week,from Wednesday to Saturday...temps were around zero at night those 3 nights,Saturday it went up to maybe 30 above..

Went to start the truck yesterday,and it had to be spun over a lot longer than when it had the electric pump assisting the lift pump on the engine..I did not have the block heater plugged in..

To my surprise the batteries I put in it spun it over full tilt even with the glow plugs being activated several times..one is a $10 flea marker Interstate group 78,the other is a 2 year old group 74..

It fired up and ran a few seconds and stalled a few times--then after I let the starter cool,I tried again,it finally chugged to life with the gas pedal floored,after like 30 seconds of cranking at least..any longer and the batteries would likely have died,I could hear it slowing down just before it finally fired up...--other diesel owners will know the sound,when the engine is firing when cranking,and the starter drive clutch is over-running,then it finally starts..

I find if I move the gas pedal while its cranking,there is often a sweet spot where it sounds like it wants to fire up,but usually holding it all the way down when its frigid works best..

All 7 of the glow plugs test good..its never had all 8 ,one wont come out,never bothered it starting in previous years..

I'm not sure if the fuel filter is clogged or not--I held off changing it to see if I can find any other issues like air getting in the fuel line (no leaks anywhere)--perhaps the lift pump is letting fuel drain back or air sneak in thru the diaphragm ?..its not wet or anything,and no sign of diesel in the crankcase--but it has been on it 16 years since I owned it too,who knows how long before ? !.maybe its "due"..?
.hoping I wont have to replace it "now",in the winter-I know it will be a sucky job I may not be up to doing..

I may just get another electric pump and run that one alone,by-pass the mechanical one..and keep a spare electric one in the truck,they are pretty cheap online..(wish they were at parts stores here!)..

Part of the reason I haven't changed the fuel filter is I expect bleeding the new one ,even if I fill it up first,will end up letting air in the system and then it'll be "fun" to get running again..without that electric pump,its a good bet it'll get airlocked during the filter change..

Truck seemed to run OK when I took it 5 miles down the road as long as I babied it,but when you stuff your foot in it ,you can feel it flatten out and start losing power..so to avoid getting stranded I just putted along slow and it ran OK..it was "surgey" at times..

I let it run awhile when I got home to help get the batteries charged back up..some weeks I don't drive it often enough to keep up with what I sap out of them starting it and using the heater,headlights,etc..
These batteries seem pretty strong and I'd rather not kill them several times and ruin them,having to crank it over so long (or fry another starter!)..

Oh yeah--forgot to add a guy I ran yesterday into told me it might be the return line going back to the tank from the injector pump is blocking up,that will shut the flow off to the pump--also mentioned a fitting that return hose goes on in the injector pump has some kind of glass ball bearing thats a check valve,he said they used to poke those out and it solved these issues on some CUCV's he used to fix in the service..
Not sure I want to touch the IP ,for fear of mucking it up..

 

[eodcoduto]

I am voting that the injection pump is shot. My 6.2 was doing similar things; taking two cycles of glow plugs smoke on start up, missing for a minute or so, plus dying when I let off the accelerator while driving when it was cold. In December I sent my CUCV pump to Oregon Fuel Injection to be rebuilt, while it wasn't cheap at $550, the Suburban fires right off now with one cycle of the plugs even when it was 9 degrees the other day. All problems have gone away and I have a lot more power and driveability out of it now.

For that last glow plug on the passenger side, the easiest way I know to change it is from underneath, then its a snap.

 

[diesel4me]

I have yet to change the filter,drove it the past few days around town to a doctor appointment and shopping,etc,and it started "ok",didn't have to spin it over very much before it fired up and ran,but it still belched some smoke out of the drivers side exhaust and had one cylinder drop out every so often till it ran about half a minute or so..


But it was near 50 degrees yesterday too--today it was 25 with a 50 mph gusting wind ,but it still started up ok ,had the same symptoms till it warmed up some though..once it warms up it smooths out and seems to run good,but perhaps a bit "lean"--I didn't dare floor it to see if it would still bog down and want to stall though..

I also have balked at trying to drain the fuel filter for fear of getting the fuel system airbound--I am leaning towards it having water in the fuel or the fuel simply jelled up that frigid day,I only added some injector cleaner I had left (Power Service white bottle),which isn't an anti-gel..I did put one bottle of "Heet" in it that said it was good for both gas & diesel,maybe that helped it if it was water or ice in the filter..

I'd think if the IP is dying ,every time I go to start it I'd have to crank the piss out of it,it would get airbound after sitting a few days..it doesn't,it fires up in less than 10 revolutions..it did start even faster with the electric pump though,and maybe the extra pressure makes up for some wear in the IP,I don't know..

I'm not putting any more money in this engine--if its the injector pump crapping out,I have a "spare" on a blown up 6.2 but it has sat outside for years,might be junk now,and I've never replaced one,and dont care to now either--this engine is going to be yanked and sold or scrapped if it gives me any more ...really sick of diesels,period..
Especially this one..it sucks to work on,and is not worth fixing if you ask me..spend hundreds on parts,and have the crank snap ,or the main bearing webs crack?..nope..not willing to risk that every mile I drive the thing..sounds like it's about to chuck a rod from day one..gets on my nerves..

Like I've stated before,I dont "need" one for what I do with the truck..

I'm going to start fooling with the two 307's I bought last summer,get them running,see if either one is good--if they are,that diesel is coming out..wish I had done that 16 years ago ,when I was a lot more capeable of fixing the truck..tired of trying to keep the diesel going--probably going to get rid of the 85 Suburban diesel too--I want an engine that starts without a hassle in winter and is cheaper and easier to fix..

 

[K5wrench]

You know, the symptoms of smoke and loss of power have me thinking.
Is your air intake, air cleaner restricted?
In a diesel, there is no rich or lean.
If you are getting black smoke, it is unburned fuel.
Now your ip pump may be over fueling, true.
It could cause these symptoms by essentially quenching the cylinder if the over fueling is severe.
But it is damn near impossible for the puny mechanical injectors to do such a thing on the 6.2.
Maybe have another look at your entire air intake.
Replace the air filter.

 

[eodcoduto]

I have yet to change the filter,drove it the past few days around town to a doctor appointment and shopping,etc,and it started "ok",didn't have to spin it over very much before it fired up and ran,but it still belched some smoke out of the drivers side exhaust and had one cylinder drop out every so often till it ran about half a minute or so..


But it was near 50 degrees yesterday too--today it was 25 with a 50 mph gusting wind ,but it still started up ok ,had the same symptoms till it warmed up some though..once it warms up it smooths out and seems to run good,but perhaps a bit "lean"--I didn't dare floor it to see if it would still bog down and want to stall though..

I also have balked at trying to drain the fuel filter for fear of getting the fuel system airbound--I am leaning towards it having water in the fuel or the fuel simply jelled up that frigid day,I only added some injector cleaner I had left (Power Service white bottle),which isn't an anti-gel..I did put one bottle of "Heet" in it that said it was good for both gas & diesel,maybe that helped it if it was water or ice in the filter..

I'd think if the IP is dying ,every time I go to start it I'd have to crank the piss out of it,it would get airbound after sitting a few days..it doesn't,it fires up in less than 10 revolutions..it did start even faster with the electric pump though,and maybe the extra pressure makes up for some wear in the IP,I don't know..

I'm not putting any more money in this engine--if its the injector pump crapping out,I have a "spare" on a blown up 6.2 but it has sat outside for years,might be junk now,and I've never replaced one,and dont care to now either--this engine is going to be yanked and sold or scrapped if it gives me any more ...really sick of diesels,period..
Especially this one..it sucks to work on,and is not worth fixing if you ask me..spend hundreds on parts,and have the crank snap ,or the main bearing webs crack?..nope..not willing to risk that every mile I drive the thing..sounds like it's about to chuck a rod from day one..gets on my nerves..

Like I've stated before,I dont "need" one for what I do with the truck..

I'm going to start fooling with the two 307's I bought last summer,get them running,see if either one is good--if they are,that diesel is coming out..wish I had done that 16 years ago ,when I was a lot more capeable of fixing the truck..tired of trying to keep the diesel going--probably going to get rid of the 85 Suburban diesel too--I want an engine that starts without a hassle in winter and is cheaper and easier to fix..

I agree that the diesel is more expensive to keep up and fuel. When diesel was cheaper than gas a 6.2 made sense but those days are long gone. I have mine because EMPs scare me and I like being able to burn about anything in it.

 

[K5wrench]

I agree that the diesel is more expensive to keep up and fuel too. When diesel was cheaper than gas a 6.2 made sense but those days are long gone. I have mine because emps scare me and I like being able to burn about anything in it.

A 6.2 in an M1009 with a turbo 400, 3.73 gears, and 33" tires nets me 17 mpg.
My 84 K5 with a 350 carburated gas motor, 700r4, 3.73 gear, and 33" tires netted 13 mpg.
That was in perfect tune.

The 6.2 still wins the economy argument.
It was and is, a damn fine piece of engineering.

That being said.. they are all 30 years old.

If mine threw a crank tomorrow.. i'd buy a 350 gas crate motor.
But since it hasn't.. and i've invested in a fluidampr harmonic balancer; it lives.

It is a slam dunk argument in favor of a simple gasoline 350 over rebuilding a broken or poor 6.2.

However, not so simple and argument to replace a good running 6.2 with a gas 350.

You will never recover the cost or make up the difference in fuel economy.

 

[eodcoduto]

Never is a strong word my friend. It all depends on fuel prices. Where I live diesel is $2.69 and 87 octane is $2.17. Diesel comes out to 15.8 cents a mile at 17mpg and the gasser would be 16.6 cents a mile with your mpg above. Not much difference at .08 cents a mile, it takes 1250 miles to save $100 with those numbers and my math. We are moving to north Alabama in 18 months and diesel there is $2.73 and 87 is $1.94. So with those numbers and your mpg the diesel is 16 cents a mile and gas is 14.9 cents a mile.
For full disclosure my daily driver is a 2014 TDI passat that last year averaged 38.65mpg. I put 21,000 miles on it in the last 12 months and track just about every tank.
My wife daily drives a 2017 Tundra and gets 17mpg out of it so saving really boils down to the vehicle you drive and where you live, but for me having lived in NC, VA, CA, and now DC over the last eight years, a gas Passat is always cheaper per mile. But I love my diesels so thats why I have two and when the 6.2 dies I’m putting a 455 Buick in it!
I gets excited about my fuel mileage.

 

[K5wrench]

Never is a strong word my friend. It all depends on fuel prices. Where I live diesel is $2.69 and 87 octane is $2.17. Diesel comes out to 15.8 cents a mile at 17mpg and the gasser would be 16.6 cents a mile with your mpg above. Not much difference at .08 cents a mile, it takes 1250 miles to save $100 with those numbers and my math. We are moving to north Alabama in 18 months and diesel there is $2.73 and 87 is $1.94. So with those numbers and your mpg the diesel is 16 cents a mile and gas is 14.9 cents a mile.
For full disclosure my daily driver is a 2014 TDI passat that last year averaged 38.65mpg. I put 21,000 miles on it in the last 12 months and track just about every tank.
My wife daily drives a 2017 Tundra and gets 17mpg out of it so saving really boils down to the vehicle you drive and where you live, but for me having lived in NC, VA, CA, and now DC over the last eight years, a gas Passat is always cheaper per mile. But I love my diesels so thats why I have two and when the 6.2 dies I’m putting a 455 Buick in it!
I gets excited about my fuel mileage.

You made my point.
The cost of converting a truck from 6.2 to anything else, even a small block which he has, and bolts right in, that cost will never be recovered on the basis of fuel economy in the life span of the vehicle.
While a small block bolts up, it will not be a free swap.

Not to mention the vehicle in question is used as a snow plow.
The difference in mileage between a 6.2 diesel and 307 gas motor pushing a plow..
That disparity will become even greater.


Now swapping for more power, less hassle, cool factor, wow factor, all good reasons.
Just expensive.

He has stated numerous times he is very short on cash.
If that is true, the best course of action is to maintain the 6.2 as long as possible.

I have no dog in the fight.
Only wish to help.
If there were something simple wrong like a clogged fuel or air filter, that is going to be cheaper and vastly easier for him to replace than a motor.

 

[bigblock454]

See my status to the left for my opinion!



(Status, not username!!)

 

[yellowK20]

I daily a 6.5 turbo in a 90 V3500 on 35” rubber with a TH400 , 4.10’s and right at 300,000 miles now .

I get 19-20 mpg running 65 mph on my 120 mile round trip commute.

It starts unplugged down to about -20 with no issues any colder then that it needs to be plugged in.

Still has the original glow plugs , injectors , and pump .

What makes my truck different? I maintain it , It gets regular oil and filter changes . I keep good matching batteries in it . (I had to upgrade my old red top Optimas to new Yellow tops for winter plowing use ) I put a new harmonic dampener on about every 100k .

I also put a quart of ATF or 2-stroke oil in every tank because these trucks where not designed to run Ultra Low Sulfur fuel , just like pre 1970’s cars were not designed to run on lead free gas .

Another thing to consider, injectors are a wear item on these things just like plugs are on gasser . A lot of pumps are changed because of a misdiagnosed injector issue . If the springs in the injectors get weak you will not get proper atomization and power, mileage , and starting will be affected .

Pump problems , when the pump wears out you will get a hot restart issue . Most of the time it will still start and run just fine , except for hot restart . So if your truck starts good when warm chances are the pump is fine and you have another issue.

@diesel4me you seem to think an old carbed small block will fix all your ills , I promise you it won’t if you maintain it like you have this diesel , it will be just as big a pain in the ass.

If my truck had been a 350 ....... well for one I could not afford to daily it and two I would have replaced the motor by now .