Gas->diesel

[79k20350]

Ok so im thinking of going to a diesel. how hard is the swap? is it worth going 6.5? i have found a few 6.5s around cheap but was wondering if they will bolt in place of a 350 like a 6.2 will. well i know alot of this has been covered before but my search button takes forever. thanks alot guys!

 

[73k5blazer]

IIRC, and I'm no diesel expert here (even though I own one), but I think the 6.5 is the same block as the 6.2, just bored out a little more. So as far as bolting on goes, I believe it's the same.
As far as the rest goes...can't help too much..never done the swap....

 

[6.2puller]

While not being entirelly wrong that is not really true either. The 6.5 is a seperate casting than the 6.2. But the differences are internal so yes the 6.5 will bolt right in where your gasser was. You cannot bore out a 6.2 to run 6.5 pistons without hitting the water jackets so that is where the differences are.

Other than that yes it is a simple swap. Make sure you get the gas tank sending unit from the donner truck and if you can get the gauges too. Other than that get the wireing and motor and have fun. A few wires need to be moved in the bulk connector but not hard. Their are plenty of guys that can help in the Diesel forum in the members sections.

 

[79k20350]

well im runnig fuel cells now. my gauges are custom. i know diesels run special tachs but why the other gauges? i am going to try to find a whole truck so i know i have everything. so is there anything not mounted to the motor that need to go with it? like filters and a pump, something like that?

 

[6.2puller]

Yes, their is a fuel water seperator and filter on the firewall or between it and the lift pump. Their is also the relays for the glow plugs and the plug controler. Basically everything from the bulkhead connector forward in the engine compartment should be pulled then you can just pull your stock stuff and plug in the diesel. Plug in the lights and heater and your done.

The guages say diesel fuel only and water in fuel light(but that wont work off your fuel cell) The majority of diesels don't have tachs and if you find one definatly grab it. You don't need the fuel sender if you have a cell.

 

[79k20350]

for a tach i was thinking aftermarket, i have one on my dash now and witout one there would be a big hole ( i have a custom dash, not even close to the stocker) thanks agian!

 

[6.2puller]

thing about the tach is you need a way to drive it. Kinda hard to just tap into the distributor and all. the stockers use a magneto typ unit on the flywheel and aftermarket generally use a sensor on the harmonic ballance. Either way it isn't as cheap as just throwing one on a gasser.

 

[79k20350]

alright thats something to think about then, im sure i could find something else to fill the hole, if not i have a spare pisece of aluminum and i could do the gauges over again

 

[diesel4me]

tach attack...

Some big rig trucks used Delco style altenators that had a "Tach" connection,somehow the tach ran off the altenator ..not sure if one of them could be swapped into a smaller GM motor or not--or maybe a 10SI altenator could be modified to work that way..I don't know that much about tachs in diesels,but I do remember selling a few of those altenators ot the parts store..

You could always put a pulley in place of your old HEI's drive gear,and mount it to run off the fan belt... ..

 

[Suprzuk]

For the tach you could put in a CS-130 or 144 alternator and then use the Dakota Digital DS-1 converter. It calibrates a signal from the alternator to run the stock (or aftermarket) tach. I am setting one up on my Suzuki Samurai right now. I have a VW diesel under the hood and have a CS-130 mounted to it. I am converting the tach signal to drive the stock Zuk tach. I currently have an 87 1 ton that has a 350 in it. My grandfather gave me his 89 burb this weekend as a heart donor (diesel). We'll see if I get around to it next summer.

Kevin