What's new
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

6.2L oil cooler lines

B.barket

B.barket

Registered Member
Joined
Jul 20, 2016
Posts
74
Reaction score
25
Location
S-West Ontario Canada
hey all. How difficult is replacing the oil cooler lines on a 6.2 diesel?. The truck is an 84' K5 4X4. I used to think it was the drivers side valve cover but it's not super wet at the cover. There is definitely a sign of some oil at the valve cover but its not super wet like everything is below the valve cover on the drivers side. As of yesterday it's essentially pouring out now at the rate of a drip every second. It's just a weekend toy but I can't drive it like this.. If I just order a new set of lines are they fairly straight forward to replace or are there special tools and know how involved?. Thanks!
 
The oil cooler hoses on my '82 K2500's 6.2 were not leaking,but were ready to fail catastrophically and destroy it,it was a good thing I decided to "delete" the oil cooler several years ago..

I have seen many 4.3 V6's in S-10's get ruined when the junk OEM oil cooler hoses failed at the metal crimp collars..
I think oil coolers killed more engines than they saved..

Those hoses on a 6.2 that go in the block above the oil filter,they have crimped collars where they join the metal tubing that screws into the block--mine had aluminum crimp collars,they looked fine on the side facing you--but when I removed the hoses from the block,I was horrified to see the crimp collars were completely GONE,like acid had eaten the metal away!..the rubber hose could have blown off there at any moment and all the oil would be sprayed out in a matter of seconds..:eek:

My oil cooler hoses went to a pair of metal tubing pipes,that go across the radiator,those were rusted and weeping too,that is what I saw at first,I thought the oil that leaked from them was the timing cover seal,it was dripping or peeing out onto the front of the engine..

I decided to just use 3/8" copper tubing with two 3/8 NPT x 3/8 compression fittings to "loop" the two hose ports together in the block and not bother having an oil cooler..

A friend who maintains the fleet of work trucks at a cranberry bog told me after they lost one 6.2 to failed oil cooler hoses,they "deleted" the rest of them on their other trucks--he put pipe plugs in the block holes,but that isn't good--there is a by pass valve in the block to let oil continue to flow to the bearings,etc,but at a reduced pressure ,so the engine wont seize up if the oil cooler or hoses got plugged up,but "looping" the ports is the "right" way to do it..

Their trucks are 1 ton dumps that usually carry 2-3 tons of berries and dirt around,I figured if their engines did not fail with no oil cooler,my lightly used daily driver/driveway plow truck wont miss the oil cooler..both of the hoses on mine seemed to have practically no oil in them too,like not much was ever going thru them to begin with..

I have scrapped a 6.2 radiator and the size of the oil cooler is kind of a joke,its a lot smaller than I expected..(I had to take it out because its stainless steel and you wont get squat for scrap if the brass isn't "pure").

Dorman sells new oil cooler hoses ,that go from the engine to the metal tubing that goes across the radiator,but those metal tubes may not be available any more--I'm not sure if they have regular SAE flare or if they are metric tubing & thread,but I suppose new ones could be fabbed up from steel brake tubing ,or even copper,if its a typical size like 3/8" or 1/2",you might be able to save & re-use the old fittings that go in the radiator and where the rubber hoses screw into them..

A shop that makes hydraulic hoses might be able to make custom hoses that go the whole route too..
If the metal fittings in the radiator look like they might not come out easily,be carful,the radiator tank is pretty weak and its easy to have the fitting tear the bung right out of the radiator instead of unscrewing..a new radiator is about $400 !..that was another reason I left mine in there and decided an oil cooler wasn't a must..
 
^^^ Thank you for that info brother. Sounds like what you're saying if I have it right is that replacing the lines are simple. But that my issue(s) may be parts availability and possibly breaking something else along the way. Thanks for the heads up about the fragility of the fittings at the cooler and radiator. If I can actually source the lines I'll make sure to be very careful trying not to wreck the rad where the lines go in.
 
Thanks fellas. On your advice I went at the lines and got them out. And It’s a good thing I did!, I found the source of the leak and l was on the verge of a catastrophe!. What I discovered while laying under the truck forever trying to see where it was coming from was that the upper part of the metal line that goes to the bottom of the engine was pressed firmly up against a sharp metal edge right at the bottom of the fire wall and it had slowly worn through. That explains why it went from a slow drip to the sudden increase in leaking. It had finally worn nearly all the way through the metal part of the line!. If the line finally completely blew out when driving it would have been very bad!. Just gotta order up the new lines and I’ll be making very sure that they aren’t touching anything when installed.. anyone reading this. Maybe check yours. One more quick question. I assume it’s probably a good idea to remove the fittings at the engine and replace them as well Since the lines are off. Or is there a high heat Teflon tape or something they can be wrapped in and then reinstalled?. Or do I just leave them alone?. Thanks again guys.
 
The fittings are probably fine, I wouldn't worry about them. If your worried about the line rubbing on the firewall again...Split a piece of rubber fuel hose and zip tie it over the oil line where it comes close to the firewall..that way if the oil line gets moved again (it might be moving due to motor torque) it will rub on the hose instead of the line itself.
 
Blazooki said:
The fittings are probably fine, I wouldn't worry about them. If your worried about the line rubbing on the firewall again...Split a piece of rubber fuel hose and zip tie it over the oil line where it comes close to the firewall..that way if the oil line gets moved again (it might be moving due to motor torque) it will rub on the hose instead of the line itself.
Click to expand...

Now that's a great idea!. Yes I will do that..
 
hey all. me again!.. just looking around on line for the cooler lines and the ones I see in some pics don't look like mine (sorry I don't have pics of my lines). Maybe the pics on line are generic photo's as I'm sure the routing is completely different for models like vans etc through the years that used the 6.2.. But just to clarify, my lines go into the rad on the drivers side of the radiator. Is that the factory routing?. Its just a straight shot from the rad back to the engine. The lines I removed only have all the crazy bends in them at the one end where they meet the engine. The front of the lines at the rad are just straight hose with a straight fitting that goes directly into the fitting at the rad. There is no pipe at the radiator end of my lines that have any bends in them at all. Before I order new lines I just wanted to confirm if my lines are indeed factory because if not, I'll have to have find a place to have a set made to match what I have now.
 
Both of my 6.2's (one is in an '82 K2500,the other in a '85 K10 Suburban) have the oil cooler ports in the radiator on the passenger side,so the hoses have to connect to two metal tubes that go across the radiator fan shroud to get to the cooler in the radiator..seems like a stupid ass backwards way to arrange things,they put the transmission cooler ports on the drivers side of the radiator,so the cooler lines have to be twice and long,and harder to route..(on my TH400 the cooler lines come off the passenger side of the bell housing area)..

GM may have moved the oil & transmission cooler ports on the radiator to the "correct" positions to enable shorter hoses and cooler lines to be used (like it should have been to begin with)--or perhaps someone decided to use the transmission cooler for the engine oil and the oil cooler for the transmission ?..
 
diesel4me said:
Both of my 6.2's (one is in an '82 K2500,the other in a '85 K10 Suburban) have the oil cooler ports in the radiator on the passenger side,so the hoses have to connect to two metal tubes that go across the radiator fan shroud to get to the cooler in the radiator..seems like a stupid ass backwards way to arrange things,they put the transmission cooler ports on the drivers side of the radiator,so the cooler lines have to be twice and long,and harder to route..(on my TH400 the cooler lines come off the passenger side of the bell housing area)..

GM may have moved the oil & transmission cooler ports on the radiator to the "correct" positions to enable shorter hoses and cooler lines to be used (like it should have been to begin with)--or perhaps someone decided to use the transmission cooler for the engine oil and the oil cooler for the transmission ?..
Click to expand...


^^ yeah it would make sense to find out that something about my set up is not OEM. I do remember the P/O telling me about how the cooling system had been "upgraded". I wonder if this was part of what he was talking about. I think this rad might be the kind that has the cooler inside the rad itself rather than an external unit. I could be completely wrong about that but I seem to remember reading somewhere that at some point the rads had the coolers inside them rather than externally mounted. Can't remember which system would be the older vs newer style. I'm laughing at myself right now for not knowing what I have but the rad is so well boxed in, top - bottom and sides with the plastic protective covers that I've never gotten a good look at the back side of my rad. Granted I've never really tried that hard to see it. I'll have to take a good look tonight to confirm one way or the other if the cooler is inside or outside the rad. Anyway. I had the lines in the back of my car and stopped into a local hydraulics shop to see if they can just make me a new set. We shall see what they say when they call me back. The guy I spoke to was not an expert and didn't know if they could replicate my lines or not
 
I have not seen any 6.2 radiators around the vintage of my two trucks with the oil cooler on the drivers side of the radiator,and as far as I know they all had the cooler made into the radiator for both the oil and transmission..however someone could have added an external oil or transmission cooler in front of the radiator too..

Perhaps later models have the cooler positions swapped around so the lines and hoses dont have be so long and difficult to route ?..
I haven't had the chance to see many of the GMT400 pickups with 6.2's or 6.5's to tell..some other members here will likely know..
 
I found this pic on line and this appears to be exactly my set up. The lines that go across the rad turn 90 degrees toward the back of the truck just like mine and the hoses connected to them look exactly like mine as well.. Is this a stock set up in this pic?. If so this is exactly how my lines connect. I removed them at the drivers side. I did not need to remove the lines that run all the way across the rad.

Cooler lines.jpg
 
Thats how both my trucks are set up..the rubber hoses screw onto those metal tubes up near the drivers side battery,if the tubes aren't rusted or leaking then you can get away with just replacing the rubber hoses...

Trying to unscrew the metal tubes might end up ruining the radiator if they are tight & rusty,the bung will tear instead first..in cases like that I cut the metal tube a few inches away from the radiator and use a compression fitting to splice a new piece on,and leave the original part in the radiator alone,provided its in decent enough shape to trust..
 
That is indeed the stock setup. If your radiator is OEM...it would be worth it (IMHO) to disconnect the hardlines at the rad. If they're fused in there and you mess it up, just buy a new radiator - that sort of corrosion implies other issues in the rad. If they pop free after applying some Kroil and drinking a beer, flush the hardlines out out with Brakleen and just put some new o-rings in there.

Oh yeah...and use two wrenches.
 
^^ Thank you for the verification fella's!. At least now I know for sure what I'm dealing with. If I can't get a shop to make me new lines I wonder if I can just order the section of lines that run from the engine to where the rubber hoses meet that that 90 degree bend in the hard lines at the rad?. Its not the end of the world if all I can order is the entire system that means the lines have to be replaced right from the passenger side of the rad all the way back. Just looking to simplify the job if I can!.
 
If you do attempt taking the metal lines off the radiator to replace them ,first I'd cut off the tubing near the fitting,because its highly unlikely the nut will not be frozen to the tubing,if you dont do that,the tubing will want to twist up like macaroni,and require so much force the radiator will likely get ruined..
(again,I am not sure replacements exist any more,you might have to make new ones from bulk tubing and re-use the original fittings if possible,they are probably metric and hard to get-but may get mangled during removal and render them useless)..

I would avoid the risk of messing with those steel tubes myself,but that's because I dont have $400 to buy a new radiator for a truck that is worth about that much running and driveable..that is another reason I just "deleted" the oil cooler period..

Instead I'd consider adding an external oil cooler,and by-pass the original,it is marginal anyways in my opinion as far as its size and effectiveness...an aftermarket one is about $100..and comes with bulk hose that uses barb fittings,which costs a lot less than factory hoses or custom made ones..
 
diesel4me said:
If you do attempt taking the metal lines off the radiator to replace them ,first I'd cut off the tubing near the fitting,because its highly unlikely the nut will not be frozen to the tubing,if you dont do that,the tubing will want to twist up like macaroni,and require so much force the radiator will likely get ruined..
(again,I am not sure replacements exist any more,you might have to make new ones from bulk tubing and re-use the original fittings if possible,they are probably metric and hard to get-but may get mangled during removal and render them useless)..

I would avoid the risk of messing with those steel tubes myself,but that's because I dont have $400 to buy a new radiator for a truck that is worth about that much running and driveable..that is another reason I just "deleted" the oil cooler period..

Instead I'd consider adding an external oil cooler,and by-pass the original,it is marginal anyways in my opinion as far as its size and effectiveness...an aftermarket one is about $100..and comes with bulk hose that uses barb fittings,which costs a lot less than factory hoses or custom made ones..
Click to expand...
It's funny how I have parted a few trucks with these lines and they were in good shape but never had anyone show interest in them.
I have thrown them away.
I might have one set from the last one I did.
 
That's because there isn't much road salt in CA...or acid rain..
Up here everything rots away pretty fast...or fuses together,making repairs a miserable chore..
 
Well. The hydro shop couldn't help me today so I went on a tour and hit every parts store around me. I visited 6 places today. 7 if you include the hydro shop that couldn't get me what I needed. Why its always the last store you visit that has what you need?!. Of the 6 parts stores I went to. 3 couldn't find the parts at all and two just couldn't have cared less to try and help. You know the type!. And then carquest auto parts of all places not only sourced the sections I need without messing with the hard lines that run across the rad. But they found them in about 2 mins and will have them for me by noon tomorrow. I couldn't believe it. Up here in Canada unless its a newer mass produced part or something more common. We typically just don't have the variety of suppliers in our back yards that you guys in the U.S have. I usually have to settle for ordering everything from far away wait for shipping and pay a ton for it with the exchange - brokerage fees etc for crossing the border and so on. I'll update when the jobs done!
 
You must log in or register to reply here.

Latest Posts

Top Bottom