3.4 swap into 91 Trooper

[geoffinbc]

Yea I just picked myself up a 2.8L trooper a few weeks back. But I will not be doing a 3.4L swap. I have a 3.1L crank already so I will be installing that with a .030 overbore and stump puller camshaft. This truck is going to be my 4X4/Camping rig.

[Jackaroo]

Did you finish the 3.4 swap into your Trooper?
I'm about to dive into a similar project as my 2.8 is a goner.

[Canyonero]

Yes and no. I have A/C so there's a condenser on the other side. Aside from that, I haven't looked. I'll pull the radiator out again today, I just put a couple bolts in to test the fit.

[CNCguy]

Hah, slight miscalculation. The Trooper engine bay is smaller than I thought. I see why people don't do the swap this way - the engine doesn't seem to fit...

At a minimum, I need to relocate my battery and get a different electric fan. I'm thinking a dual 10" instead of a single 15". Less CFM, but still adequate.

I'll make it work. Just you wait.

Got room for a pusher fan?

[Canyonero]

Hah, slight miscalculation. The Trooper engine bay is smaller than I thought. I see why people don't do the swap this way - the engine doesn't seem to fit...

At a minimum, I need to relocate my battery and get a different electric fan. I'm thinking a dual 10" instead of a single 15". Less CFM, but still adequate.

I'll make it work. Just you wait.

[geoffinbc]

Sorry I meant 3/4" my bad. Always run a large pickup. Dont be discourage by the stock pump. It may have miles but that does not mean it is bad. But dont think you can just drop it in and go. Be sure you disassemble and inspect. Also verify the clearances and lash in the gears. There may be specs the the 60*V6 power manual and I think the pages are on this site somewhere. Or if you want try a local source for a Melling pump or a stock reman pump and go ahead with your build and return the Melling HV pump in the mean time.

Just something to ponder... A member on S-Series used an HV pump on his blown 4.3L build. The engine lasted only a few thousand miles before it ate itself. The problem ended up being the HV pump which was causeing excess airation in the oil. He never rebuilt the engine he ended up parting out all the components. My friend Dan was going to buy the blower for his 02 S-10 so he would know the guys thread I will try and find it.

[Canyonero]

I have the stock pump that came in my engine (70k miles they tell me) and the 3/4" 4x4 pickup (Melling 245S). I guess now it's a matter of exchanging my M134HV for the regular M134 - or saving the time and just using my original pump, returning the HV pump for refund. My old man tells me that I'm already counting on the rest of the engine to be good, so I might as well trust the original oil pump and I think I agree. I finished pulling the engine today and taking all the bits off it, so now I'm waiting on the oil pump to get the new engine together.

[Ed_Mc.]

I believe you'd want to use a Melling M134 (or equivalent) oil pump with the larger-diameter (3/4”) inlet hole, and (as discussed earlier in this thread) for 4WD applications, the Melling 245S pickup tube/screen (or equivalent such as Sealed Power 224-14266).

And here's something I found on the www.paceperformance.com site regarding the HT 3.4 crate motor:

"4WD oil pan is part # 10099979, and 4WD oil pump screen is part # 10118626"

I'm assuming that since that P/N was meant for a 3.4, it's a 3/4" tube. But you'd have to verify that to be sure.

The oil pump with 5/8" hole (such as a Melling M95B) isn't recommended for a 3.4 and if I were working on a 2.8 or 3.1 that came with the smaller pump, I'd upgrade it anyway, just on G.P.

HTH...........ed

[geoffinbc]

Ok run a stock sized pump. Then use the large edit:3/4" pickup tube. A good quality filter will ensure protection.

[Canyonero]

Yeah, they have a 90-day return policy, I'll check into it.

[geoffinbc]

Well if you can take it back I would. HV pumps do more harm than good. First you run the risk of sucking the sump dry. Second the majority of the oil simply spews out the presure bypass because the pump it trying to force so much volume into the oil gallies that it pops the pressure spring. This resulting bypass heats up the oil. It is also a big waste of horsepower.

A stock pump will supply MORE than enough oil to the enigne at 6000RPM all day long. If you were to go racing with the thing at say 7000RPM then all I would suggest is get the stock pump precision machined for tighter tolerance and put some shims under the pressure relief spring. And then eliminate the oil filter bypass. But never would I got with a HV pump.

[Canyonero]

How much larger? Looks physically identical, Not sure about flow specs other than what it said in the description: "standard pressure" and "20 percent over stock volume".

Part#: MEL-M134HV
Brand: Melling Engine Parts
Product Line: Melling High Volume Oil Pumps
Oil Pump Style: Wet sump
Oil Pump Volume: High volume
Oil Pump Pressure: Standard pressure
Notes: Approximately 20 percent over stock volume.

[geoffinbc]

Eww you should't have done that. HV pumps are a bad idea. How much larger is this pump you got? You should have kept the stock pump but of course get a new one or inspect the old one.

[Ed_Mc.]

http://www.autozone.com/in_our_store...ump_screen.htm


This would be the correct tool for the job. It clamps around the pipe so you can drive the pickup onto the pump body. I suppose you could also find a chunk of pipe or an old socket which has an I.D. slightly larger than the O.D. of the oil pipe; then cut the pipe/socket lengthwise so it can be used to drive against the "knob" on the pickup pipe.

But I expect the real tool will do a better job! Autozone 'rents' their tools for free, the deposit (which is actually the purchase price of the tool) is refunded when you return it.

Some good info here, too, scroll down to the "installation" section:

http://www.aa1car.com/library/us1097.htm

HTH & Happy Turkey Day..........ed

[Canyonero]

What's the best way to press the oil pickup into the pump? I put in a new high-volume pump while I was in there.