Hi,

I will be looking at a "3.4 Motor to swap into my RS this week. The motor isn't in the car so how do I tell that its a 3.4 and not a 3.1, 2.8 etc? I'm not sure if the intake will be on the motor either.

 

powersteering pump w/plate~cover for icm & coil paks to sit, and erl pan

good to be able to pst for once

 

EASIEST WAY TO TELL A 3.4
Is to look for the cam sensor, top dead center of the engine BLOCK behind the timing cover set up.
It's right there & it has wires running outta it about 12" in length. That sensor reads cam rotation to send signal to distributor set up & fuel pump.
IF that not there, not a 3.4.
When ya do your 3.4 swap, leave that sensor alone. One less leak if just tie wires & be done.
Happy hunting.
I paid $800 & $900 for mine, very low milage long blocks. Get all ya can, as all stuff is important. The power steering pump swaps over, ya use the 3.4 injectors & ya use the exhaust manifolds and FRONT 3.4 BALANCER & THE FLEXPLATE/FLYWHEEL

 

As ked85 said, cam sensor on top.

Also forgoten by him, but a crank sensor on the passenger side of the block, down low by where the starter mounts.


If it has all the accessorys on it, their are many other ways to tell.

 

That detail wasn't forgotten.
You answered my point in that omission, due to the crank sensor set up is so easily removed or damaged & tossed.
Make sure you do buy the most complete 3.4 long block package ya can.
By doing so, you reap the most complete correct parts for swap/upgrade/barter/selling.
Make sure you do not throw away all the good 2.8/3.1 parts in your process of upgrading powerplants under your hood.

 

I'm looking at a 100,000 mile motor complete with "all accessories" for 300.00--can hear run. The guy had another one with 70,000 miles on it but I waited too long. I'm hoping to NOT need to tear it down right away and just swap it in. My current 3.1 has 171,000 miles and runs great, burns no oil but leaks oil like crazy to the point that I don't park in peoples driveways! The price seems good, I just didn't want to get screwed. Thanks for all the info!!!

 

Maybe it's just me, but there's no way I'd ever just 'drop an engine in'.

I mean, it's ALREADY OUT OF THE CAR!! THAT'S LIKE 70% OF THE WORK DONE!

I'd drop that 3.4 in - after I had gone through the motor, cleaned it up nicely, checked/replaced the main/rod bearings, definetely a new timing set in it! I would do that, at hte very least - any problems in the top of the motor, you can deal with while the motor is still in the car. Try replacing a rod bearing while the motor is in the car still!!

 

That's a very fair price for the milage.
Doward does have a good point.
My first 3.4 in Firebird soliders on. I started with a 50,000 mile engine.
I need redo the timing chain while I'm doing some stuff, shortly.
Replace all wear parts when ya can. And also clean all sensors. You'll also redo 100% of the vacuum lines.
IN the end, it is a very simple very detailed engine engineering project.
Read my swap thread in tech section.
Totally worth the outcome.
Best tip...
Repair anything ya can on the current engine in car. That way ya know it works after the swap.
PS Tranny performance is greatly reduced after ya do the swap
In other words, it tends to kill the in car tranny unless it's been rebuilt recently. I'm gonna be on my third tranny after the 3.4 swap, shortly.
Your car will pull like a freight train after the 2.8->3.4 Long Block Swap Boogie.

 

What car was the 3.4 from? GM used plenty of 3.1s in front wheel drive applications w/ distributorless ignitions. If its a 3.4 from an F-body, it will have a casting of an 'F' on the driver's side of the block. I would look for that. I only bring this up because you didn't mention what car the motor came out of.

 

I'll throw this out.
On one of my 3.4s I DO have that "F" cast passenger side engine block
NOW the 3.4 in my Firebird, same vintage (1995) DID NOT have that "F" cast in block.
GO figure
You believe that's what the "F" means? I say Flint, MI engine plant!
1993-1995 (First part of 1995 model year production run) F Body only really works right for the Swap Boogie!
Not worth "machining" for a FWD 3.4 block.
PS No longer made is the brand new RWD F Body 3.4 crate engines. Production has stopped. Bet that plant now making the "World Class 60*V6" as seen in 2005 Caddys!

 

Oops, I should have said passenger side instead of driver side. In the pic, the 'F" is just below cylinder #5. That's weird that you a have a 3.4 block without the F casting.

 

also in that picture, you can see the crank sensor hole, and if you look hard, you can see the cam sensor hole.

For sure a 3.4

 

I may decide to go through the motor, just really busy right now. Pulling the motor from the car takes 1 day max, done 'em many many times, so I don't feel thats a big problem. Funds are a little low right now and I'm saving some dough for other projects. Anyway, I picked up the motor yesterday, complete except starter. It has the funky looking intake I've seen on 4th gen cars, and other features you guys have mentioned, so I'm pretty sure its a 3.4.
heck...now I feel guilty not going through it!! Maybe a quick rebuild...I just gotta keep the wife from finding out.


thanks again.

 

Make sure you install new seals on valves in heads, to control oil leak into cylinder, at very least.
Also tap weld the oil pickup into the new oil pump, with screen set about 1/4"-1/2" off pan floor.
Make sure you get balancer snout sleeve ($4) to keep any oil leakge there under control. Ask for one for a 2.8, same thing.
Study what ya got under your current hood, in end, duplicate it using the 3.4 long block as foundation.
One guy CaliCamaro, has lots of brand new GM 3.4 parts for sale. Like the stuff ya now need.