Thoughts in GM Vortec V6 in a Yale forklift.

[fastline]

Bought a "not running" forklift off a company recently. They repair equipment but did not know specifics about this fork other than it has been there 3-4yrs and needed a new home.

We did a little work and determined the reason it was parked is likely due to a major water leak into the crankcase. The initial oil stick test looked fine because the water was settled out. Oil was "clean"...lol When cranking, we were not getting much vacuum because lifters were not pumping. Actually top end oiling was not really happening. We checked oil again and got the gray nasty. Pulled the filter cut it open and it was clean. Started to drop the oil for a cleanout thinking it "might" be condensation but green coolant was the first thing I saw dribbling so I didn't even drop the oil. There is no point as it is obvious we need to decide some things.

I'd like to know how special the engines are for forks? I have read valve seats are special on LP engines? Do they also turn up the compression and cams to take advantage of the LP octane?

I did have it running s short while. It did not have any crazy rod knock, just was obvious it was not running on all cylinders and seemed to have a LOT of blowbye from the oil filler, but it has been sitting so just not sure on that one.

These engines are not the most fun to tear into while in chassis, but I have seen MUCH worse and seems reasonable.

Thoughts on what to do here? Are they known to blow the head gaskets? I think it has about 5500hrs if the meter is right. Chassis appears to jive with that. All other vortec V6 machines we have had were very solid. One Hyster would actually do a burn out about anywhere. Was VERY amazed with the power it had and convinced someone put a hotter engine in it.

 

[RZucker]

If it has an aluminum intake manifold it may have corroded around the water outlet holes at the front of the heads leading to the thermostat housing? Or had the intake gasket rot out at the rear of the heads

 

[fastline]

Hmm, have not had these issues but it does have an Aluminum intake. Are these known for head gasket issues? I mean, it could be any list of things, including freeze breakage on the block but all I see is green coolant and no signs yet of freeze damage.

Hoping for a simple fix because we could sure use it right now!

 

[Delmer]

What are the odds it froze, and then somebody added the antifreeze? Not that likely in CA is it? or maybe more people run straight water in their engines than here? You have nothing to lose by taking it apart, except time and maybe not finding anything definite in the process. You could try to narrow it down to see which cylinders are missing.

 

[4x4ford]

If it’s like the auto engines I’d definitely check for bad intake gaskets those used a plastic with rubber insert that would fall apart and start leaking

 

[fastline]

Any ideas where to find the important info about the engine? series, model, etc, etc? There was some talk inline that the industrial engines are certainly setup different. Low HP, high torque, low RPM, hardened valve seats, etc.

 

[Birken Vogt]

Any ideas where to find the important info about the engine? series, model, etc, etc? There was some talk inline that the industrial engines are certainly setup different. Low HP, high torque, low RPM, hardened valve seats, etc.

In my experience the make a couple thousand of them and then promptly pitch all records into the trash can. Assume you are on your own but maybe you can be pleasantly surprised.

The usual suspect for manufacturer of record of that engine would be PSI, Power Solutions International, but they are not known for being helpful or forthcoming with information.

I have had most success with parts for that one at the auto parts store by calling it a 1992 Astro van 4.3 but go there with parts/gaskets in your hand to verify before you buy.

 

[fastline]

LOL, it's that the truth! You walk into a big chain parts store and you get the "what's the year/make/model".... If you say "an industrial 4.3", they will say "we don't have anything".... So you say " well Bob, I am working on a 2001 chevy astro van"......

For the reasons mentioned in the posts above, I would like to revive the engine if possible, since I know it is the right engine for it.

There is some indication these forks had engines tuned to about 90HP and I found some industrial 4.3s doing 180HP on LP..... That could explain why that one Hyster we had would spit fire! I mean, that girl would RUN.... Maybe I DO want to swap that engine! LOL Not many applications where you need all that power but it sure is fun!

 

[fastline]

So I have the intake manifold and right head off. There are just too many things not adding up yet and I don't usually repair an engine without knowing all then when and why. Is there anyone here that knows these 4.3s really well? Should I ask in the general area? I have a frozen valve, coolant oil, no coolant in exhaust, oil sitting on two pistons when head removed, piston and ring clearance that gives me pause.......

And it is obvious this engine has been rebuilt pretty recent. The Felpro gaskets look very newish, yet the pistons appear to have lots of play in their holes. And the bores looks near perfect. No steps at the top at all but I am going the measure them just to get more for the story.

 

[Birken Vogt]

It's just a Chevy 350 minus two cylinders. No specific knowledge required. Probably just some hack was in there before you. Rebiuld it right and you should be good to go.

 

[fastline]

The heads have heat tabs on them, which is indication a professional facility has touched them. I don't know if that is just for the heads, or what. There are numbers on the heat tab and I was at least hopeful they meant something to the right shop. At least we know it didn't overheat.

 

[TD24]

Have you thought of taking the model and serial number to a Yale dealer and trying to buy a service and/or parts manual for it.
Equally, with the known model, there are several industrial engine re builders that could shed some light on it.
Find some numbers and post with a couple of pics, R side-L-side, with engine visible. Might dig you up something.

 

[fastline]

Well....... The plot has shifted. I put my machinist hat on and grabbed some of my mobile test tools and confirmed the block is punched 30 over, measuring a nominal 4.0305 with about .002 taper and .0005 egg. HOWEVER, pistons are STD!!! Ring end gap (because she is so loose that I can get to the top one) measures about .140, and a target of .016-.020.

This engine is coming out. I mean, who does that? I can only imagine the type of person that built this engine!

So....I am looking to install a different engine. So now I need to find resources to spec the old engine. I can confirm the engine, by the MFG specs, was only pushing less than 100HP (not sure at what RPM yet), so I would think there are several that could work. Right now I am considering a light truck engine.

However, I know hardened seats are the norm for LP and not sure if that is BS and ALL of them out there are really the same, or if not, how long would standard seats hold up? The truck will not get many hours under me and I will probably keep it for quite some time. I can only estimate about 10hrs/mo max.

I did look for numbers on the block but did not come up with much. I have one head off and have a GM part# but that is only so much help. Because it is LP, I should be able to dial in the jetting very easily, but it has electronic timing so I am not yet sure if that will need to match the cam or if we will run into issues there.

 

[Delmer]

I'd pick up a rusty Astro, or engine out of one at a junkyard, transfer the accessories and run it. I wouldn't worry about the cam or heads. Less HP than the gas version, potentially lower compression ratio than the LP version, if it fit's let it go.

Sell the old/new engine parts, just not to the same guy.

 

[Birken Vogt]

Yes, I agree with that low of a power setting it is not going to matter what hard parts you put in there.

Even valve seats, I believe standard unleaded valve seats should be fine for propane and at low power they will never get hot anyway.

I want to know how that thing sounded with STD/030 parts mismatched, when it was running in more or less one piece.

 

[fastline]

We had it running for a bit. Surprisingly smooth sounding! The bores really are smooth and nice and I could probably massage the block to run just fine on 30 over pistons but then I have the time/cost in getting pistons, pins, crank bearings, etc, etc, etc. If I needed a brand new engine and going to run it till broke, I would go that route.

The truck engine has no blowby, instant 60psi cold oil pressure, and now the task is figuring out how to get everything adapted.