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Melchior
06-28-2007, 03:26 AM
Without going into detail...

I need a new head. No mechanical failure, just some broken bolts from the manifolds. The engine has 246xxx KM on it (about 150k miles)

For the cost of buying a head or getting mine rebuilt, pulling the existing head, installing the new one...

Is it stupid not to go further and just pull the engine and replace it? I can't do this myself, it's not an option, so I'd be looking at the cost of a clip and then the labor to remove the old and replace the new.

Now, i thought this would be a huge difference but the local Mr2 mechanic I asked for advice thinks it's basically a waste to get a whole new head and not rebuild or replace the bottom end.

If it helps the car has never been modified beyond a turbo timer and a BOV.

andy
06-28-2007, 03:41 AM
if your paying for labor, I would just get a rebuilt head with a nice metal headgasket and let it run another 100k espicailly since you havent modded it.

Melchior
06-28-2007, 03:49 AM
I can picture what's involved with the removal, but in the real world what type of labor would I be looking at, 10 hours?

TEAMFaint
06-28-2007, 04:10 AM
Okay!
First thing!

You own an alltrac. You dont need a clip. Just the engine + transmission will do.

Second. Its hella cheap to get a shop to do the swap. JDM Source in Calgary, Alberta does 3SGTE swaps for like $600-800 labor wise. Its not that hard.

Replace the transmission as well while you are at it, may as well.


Where abouts in Canada are you?

tw2
06-28-2007, 08:00 AM
Do a leakdown. I was in the same position as you except my intake valves were leaking. The block was 100% fine so there was no point whatsoever in replacing it. The tranny had just been rebuilt by the last owner so I pulled the head myself, disassembled it myself, had the shop seat the valves and remove a couple of broken studs, mill it and I put it all back together myself. Cheap, high quality work by the shop and I know what I did so there is no mystery there.

If you only have some broken studs you do not need a new head or rebuilt or even remove it depending on how bad it is and where.

Melchior
06-28-2007, 08:23 AM
Yeah, maybe i'll get lucky and someone can help pull them out. I don't trust myself to pull the head, and don't you have to get the block milled as well when you replace the HG?

Locations of the breaks are:
Top left and bottom left are clean brakes, bottom side closest to the collector point on the manifold (second from right) is stripped, can't get a nut on it. Others are either out or fine.

Melchior
06-28-2007, 08:25 AM
Okay!
First thing!

You own an alltrac. You dont need a clip. Just the engine + transmission will do.


Where abouts in Canada are you?


In Vancouver

As for the clip, I wouldn't buy an engine without one unless I really trusted the importer (None around here I trust) I want to *know* i'm getting the miles advertised. Other than getting a clip with odometer attached, you're taking a gamble, and what's the point of spending 2k+ on an engine that might even be worse than mine or even have higher mileage? There is zero way to prove the claims a shop can make about engine mileage on a JDM engine if you don't have the car.

tw2
06-29-2007, 11:33 PM
You do not have to get a head milled but you do need to ensure that it is absolutely flat, has no defects and has the correct roughness. If all of these things are tested fine then not to worry. As far as engines go I always recommend getting anything rebuilt whether it is your own if possible or a new one. There is NO WAY you can know accurately the history of a new engine. The only way to know its condition is to dismantle it and have a very good look in which case you might as well have done it to your own engine instead.

alltracman78
06-30-2007, 12:37 AM
Why even pull the head?
Get a leakdown test done.If it's good, see if you can find a shop that can drill out the broken studs.
I've done it on mine.
Have them install inserts instead of helicoils though.
Much stronger.

Melchior
06-30-2007, 12:46 AM
Actually, that's the real issue. I'm having a hell of a time finding a place that will touch the broken ones.

I guess my thinking was, if i'm going to end up spending weeks searching and then paying $500 to remove the 4 ruined studs and replace them, why not spend the extra 3-400 and just get a completely new top end, and get a new HG as well.

1990CelicaGT-S
06-30-2007, 12:50 AM
By the sounds of it you want to replace the head because of the broken studs. The old studs can be removed and new ones put in at almost any shop. I ended up breaking every stud on a Dodge Durango this morning. A lot of them needed persuasion to come free but they all are now.

tw2
06-30-2007, 04:47 AM
I drove to my local friendly welder who let me take off my turbo and downpipe in his workshop, take the manifold off, he then mig'd a 22mm nut on a broken exhaust stud after I had soaked it in pb blaster for days and it came out with the turn of a spanner. The whole process took a pain staking 2 days and cost $10. If it has to be drilled it is another story. You really do want an auto shop to do them as drilling something much harder out of alluminium is not a very easy process. You are correct though if someone is going to charge you $500 you might as well pull the head off and replace everything if it hasn't been done recently.

The alltrac sucks since it is AFM and it is hard to rig something to allow you to drive it with the turbo off. My old car was MAP so you could just drive without an exhaust, turbo manifolds anything to get stuff repaired.