6.2 Upgrade, HO Water pump and serpentine belt system

[buff_dog70]

Going to try and upgrade my 1982 Jimmy with 6.2 diesel to a Serpintine belt system with the High Output water pump (1997+). It has the ability to pump 130 gpm vs stock 87 gpm.
Before I dissassemble my running vehicle, does anyone know if the HO pump bolts up without modification? The HO pump was designed for the 6.5 engine, but I think it will fit. I know when it runs with the serpentine system it turns the pump in the opposite direction than older type water pump.

Also I saw I might need the twin thermostat system, does this bolt up without modification, I was going to the junk yard to go look for one?

I think I have serpentine stuff but was wondering if anyone had any good pics or walkthrough of for this mod.

 

[Russell]

I can't comment on the dual thermostat assembly other than saying that it may not be worth the money it costs to install it for the extra performance it offers. I run a single thermostat on my 6.2L which runs wide open throttle most of the time it is running, and often with a rad that is half plugged with mud. I never overheat until at least 3/4 of my rad is plugged up, even on a 95F day.

As far as the pump and serpentine stuff goes -- I was able just bolt on my HO water pump and serpentine belt drive assembly without any problems on my 1982 block and heads. I did use the backing plate for the pump from my 6.5L donor truck, but I don't recall there being any difference between the two.

 

[buff_dog70]

Backing plate?

I didn't know I needed a backing plate, or that the 6.2 had a backing plate. I'll look for one on my 6.2 or do I have to have still haven't disassembled my Jimmy. Or I will start looking for 6.5 donor parts (Backing Plate and if I can find the dual thermostat assembly. TDR says the dual thermostat assembly can increase block coolant flow by 74%, maybe I don't need it. Maybe just run the serpentine with the HO pump no dual thermostat. Just thinking.

 

[6.2Blazer]

I believe what is talking about is that the water pump is attached to this backing plate. You don't really just unbolt the pump from the engine block like most gassers, rather you unbolt the backing plate from the engine and then unbolt the pump from the plate.

I like the idea of the serpentine belt but not quite sure if the HD water pump is really necessary unless you had a built up turbo engine??? My '90 with a stock replacement water pump and stock replacement radiator never gets above 190 even under sustained heavy throttle on the trail.

 

[buff_dog70]

Still have questions.

Thanks for the input.

So is the 6.2 backing plate different than the 6.5 backing plate?

Do you think it will hurt if I go with the HO pump, too much pressure or something like that?

If I can find one for the right price I would like to eventually get a Sidewinder Turbo kit. Still need A/C where I live and the ATS you have to get rid of the A/C.

 

[Russell]

No harm in improving your cooling system The HO water pump is well worth you time, and is what I did with my truck as well. I don't think there is any difference between the two backing plates, but the one I had from my 6.5L was less corroded so I used it instead of the 6.2L piece.

I actually kind of regret having to convert my truck to non-AC to put the turbocharger on it... My heater does not really work very well any more due to my cover plate on the firewall not sealing properly any more after just bolting some tin on to convert it. I also ran into clearance issues with the downpipe to the frame and had to run my exhaust on the outside of my frame rails. If I was to do the swap again, I'd run a Banks sidewinder kit as well. They can be had for under 1k, which is cheaper than the GM-3 was for me when you consider the cost of my exhaust setup.

As far as the dual thermostat stuff goes -- If it fits, run it! If it doesn't, no huge loss, the single thermostat does the job just as well.

 

[buff_dog70]

Serpintine Belt upgrade will it fit?

Now I am questioning if the parts I have will be able to run the serpintine belt system. My parts came off a gas vehicle, did they make seperate serpentine system for the 6.5 diesel? Don't want to disassemble and find out the hard way it won't work.

If it does fit then the plan is to run HO pump, serpentine system, one thermostat. I'll try to take some pics and get them posted.

 

[Russell]

Gas engine parts definitely will not fit, sorry to be the bearer of bad news... Can't run an HO water pump without switching over to serpentine with the matching reverse rotation cooling fan

 

[buff_dog70]

Does any one have pics of the right parts?

Does any one have pics of the parts that will fit a diesel? Here are some pics of the stuff I have. I did forget about the reverse blade fan though, thanks Russell. I didn't take a pic but I have the old reverse pump, and the serpentine pulley that goes on that.

 

[buff_dog70]

Gas parts don't fit?

I just wanted double check that gas parts don't work. The local NAPA guys seems pretty knowledgable, he thinks that since the 6.2 was built on the existing 350 cubic inch block the bolt ups for these serpentine attachments would be the same. Russell have you tried this upgrade in the past?

 

[thedrip]

Your knowledgeable parts guy has two engines confused. He's got the 5.7L Oldsmobile Diesel confused with the 6.2L Chevy (Detroit) Diesel. The olds was based on an existing 5.7L Oldsmobile engine with new heads. The 6.2 was a ground up design, with the restriction that it physically fit in the engine bay using small block Chevy engine mounts and transmission hookup. 350 chevy accessories will not fit on a 6.2. for that matter, 350 chevy accessories won't fit on a 5.7L diesel either, as its actually an oldsmobile.

This is a super common point of confusion among people who know enough to be dangerous, but not enough to be right.

 

[AJMBLAZER]

This is a super common point of confusion among people who know enough to be dangerous, but not enough to be right.

Amen.

 

[buff_dog70]

Thank for the clarification

Thanks for the clarification, before I tear everything apart and subject myself to hours of frustration. I posted in the WTB classifieds for the correct parts, guys responded said he will have more information on Monday. What do you think a fair price for the parts will be? So I can't even use the pulleys? I will postpone the my upgrade till I have the proper parts.