Engine rebuild - tips and suggestions

[MrTibbs]

Hi people,

I've more or less got the engine out of my parts car and am planning to rebuild it and put it in my car which I'm going to do a lot of work on when my garage is free.

I got the engine running when I got the parts car (it had a dead DME). All sounded OK with no worrying noises or anything immediately obvious, but I didn't run it for long. At that time I didn't have a compression tester, and I've since taken the intake off and stripped the car so I can't get it running to test the compression.

The car has 118k miles on it, and had sat for about a year I think before I got it. When I drained the oil it looked OK, with no obvious sign of coolant in it. Similarly, when I drained the coolant there was no sign of oil.

My question is really what would people recommend I do when rebuilding the engine. I'm not after huge power gains (though any obvious easy improvements would be good), just want to do what's needed to make a good solid engine I don't need to worry about. I'm planning on giving it a good clean, polish the intake manifold and paint the cam tower as well for some engine bay bling.

My list of things to do so far is:
* Belts and rollers
* Rod bearings
* Valve stem seals and lap valves
* Head, intake and exhaust gaskets
* Rear main seal
* Piston rings (are these a good idea in all circumstances, or just if they have too much clearance?)
* clean all grounds, replace charging and starting wires, and add an additional ground
* Use the best motor mounts or replace if can't find 2 in spec
* Cap, rotor, and spark plug wires

Any thoughts? Particularly from those of you who've rebuilt one of these engines. I guess it'll become clearer what needs doing once I start getting it apart.

Mike

[RedBaron]

If you are pulling the engine, do it right and get the complete Victor Reinz seal kit for the top AND the bottom. This would include seals for the balance shafts, oil cooler, AOS, etc. If you are pulling the engine, you might as well check the clutch and see if there is a lot of wear. Also if you are doing the rings you might as well do the main bearings (even though replacement is not necessary.) If you are doing the rollers and belts you might as well change the water pump. If you have no interest in using the A/C it is a good time to remove it and reseal your power steering rack. I would also inspect the Control Arms for wear as well as the whole front suspension. Since you are pulling the transmission you could also check out the CV Joints and reseal/repack.

[Cocacolakidd]

Make sure you properly hone the cylinders so the rings will seat in -

Sunnen AN-30 Honing paste, plus the felts that are available for a stone hone - Some use the green Scotchbrite pads with success - Cover the stones on the hone with the pads so the stones never touch the cylinder walls - hone very little, just until the cylinder walls are dullish in appearance...

[uvachief]

Originally Posted by RedBaron

If you are pulling the engine, do it right and get the complete Victor Reinz seal kit for the top AND the bottom. This would include seals for the balance shafts, oil cooler, AOS, etc. If you are pulling the engine, you might as well check the clutch and see if there is a lot of wear. Also if you are doing the rings you might as well do the main bearings (even though replacement is not necessary.) If you are doing the rollers and belts you might as well change the water pump. If you have no interest in using the A/C it is a good time to remove it and reseal your power steering rack. I would also inspect the Control Arms for wear as well as the whole front suspension. Since you are pulling the transmission you could also check out the CV Joints and reseal/repack.

Just curious, why do you recommend replacing the main bearings? I've never heard of them failing.

[Cocacolakidd]

Well if you are in that far why not - The main bearings normally do not fail, without excessive mileage and excellent up-keep they last quite awhile - Except number two mains. Have a oil pressure drop where the mains do not receive constant oil pressure and number two bearing goes out very quick. Especially if it is an older worn set.

[Techno Duck]

Depending on the condition of the cylinder walls i would not bother reringing the motor. Replace the mains if you want.. adds about $250 to your total cost but no better time to take the crank out than with the engine on a stand. Dont forget the bearings for the balance shafts, front and rear. The rear bearings will probably have very little if any wear with 100k miles on them but again, no better time to replace them.

I would just do a standard rebuild, dont go crazy with head, crank..etc work. Not worth while for a street motor. The only thing i would recommend is lightening a stock flywheel.

[MrTibbs]

thanks for the suggestions. Forgot to list the oil cooler seals and Aos. Will swap the brand new clutch in from the engine in my car so that's all good. Was planning to reseal my spare steering rack too. Control arms and joints are all brand new.

Mike

[carlege]

If you removed the crank girdle i have heard about an issue with re aligning and sealing it so you avoid possible oiling issues.

I would look into it more. This has been discussed on Rennlist

[Cocacolakidd]

Not a big deal with replacing the Crank Girdle as it will only go on one way - it's a machined alignment so it is easy to get correct.

There is a sealant required that goes on as you are re-setting the crank girdle - The sealant is applied to perfectly clean surfaces between the girdle and block (See work shop manual for more details).

000 043 019 01 - Silastic 730 RTV - sealing compound...

[MrTibbs]

Managed to sneak away from work early and spend a couple of hours in the garage. Got the engine out by lifting the front of the car a bit more and pulling it out from underneath. I was surprised at how easy the engine is to slide along.

Just before I packed up, I thought I'd start getting the clutch off. The bell housing bolts all came out very easily (using a 2 foot breaker bar), and the starter motor was also easy enough to get off the engine.

The engine looks pretty clean with not much evidence of big leaks so far, which is good.

Looking forward to whenever I get a chance to do some more tearing down.

Mike

[MrTibbs]

Ok, so I've managed to get the cam tower off (all looks Ok to me), and today got the head off.

There's a lot of carbon build up, but the insides of the cylinders look good - didn't turn it over as I need to clean some dust that fell in when I was getting the head off out first. I could see number 1 and 4 cylinders, and number 1 looked fine, while number 4 has a small scratch.

I've put some pics below, but basically I'm thinking I might not re-ring the engine, but instead replace the rod bearings, lap the valves and replace the guides and replace the gaskets etc. Oh and remove the carbon of course.

I've not rebuilt an engine before - you guys got any comments based on the photos below?

Mike

[Cocacolakidd]

I have not used it yet myself, but I hear from several others here on the board that "CRC Gasket Remover" does a fine job getting the top of the pistons very clean. Plus the CRC Gasket Remover is Aluminum friendly. You use it like thick paint remover, and repeat a few times per cylinder. Once you are able to hand crank the motor over one would have two cylinders up, and two down. First spread a coating of grease around the edges of the two up piston/cylinder to keep any thing from getting down between the cylinder and piston skirt/side. After all of the cleaning is done on the two up pistons then crank the motor until those two pistons are down, and clean all grease off of the sides of the cylinder walls and wipe the piston tops clean. Then start on the other two.

[v2rocket_aka944]

use plenty of oil to get the rings in

[cjpacitto]

Don't "paint" the cam tower, powder coat it. It will look better and be far more durable.

Your water passages look awfuly rusty for an aluminum engine. Make sure there is no debris trapped in them.

[djnolan]

Another minor detail is the rubber hoses for the cooling system, power steering and ICV.

[HondaDustR]

Correction. You need Locktite 574 anaerobic sealant for the crank girdle. I wouldn't try anything else unless I knew for sure it was a proven alternative, given the criticality of that part of the oiling system.

If you don't plan to do the rings, avoid removing the pistons if you can. The rings most likely wear themselves to the exact shape of the cylinder after this many miles and probably won't seal as well if reinstalled. I found AN-30 and felt alone on used cylinders is pretty ineffective. A light green scotchbrite hone followed by the AN-30 works very well. Scotchbrite alone leaves a bit of a rough surface. It might work ok, but the AN-30 lapping really made them look "right". DO NOT re-ring used alusil cylinders straight up. They have a snowball's chance in hell of breaking in and sealing, and you'll just be worse off than when you started. 118K miles is still pretty young if the motor has been well cared for, esp if it doesn't see alot of high rpm on a regular basis. You can read my project thread for my rebuild adventure if you haven't seen it already. Project 924 S engine replacement

Just don't forget...it's stupid easy to do (insert any job here) on an engine stand, so do it now if you have any doubts as to whether you should, esp gaskets/seals...oh and nothing ever fell off the floor.

[MrTibbs]

Thanks,

Honda - I've read your excellent thread a few times - it's what inspired me to re-build this engine really. I think I'll leave the engine with the rings that are on there and see how it goes. I'm planning to try to do a reasonable job, but don't want to spend a fortune on rebuilding it and as it's my first attempt might try a more straightforward refresh job first.

It's certainly a lot easier to get at the engine with it out of the car - I'm thinking that a clutch job may well be easier just taking the engine out.

cjpacitto - I'll give them a good flush to make sure there's nothing trapped in them. I think it might be the flash that's making some pretty cruddy oil look like rust but will give it a closer look when I'm next at my garage.

Will keep you all posted on progress, and ask a lot more questions I'm sure.

I need to check out where I can get powdercoating done round here - I'm a bit tight for cash at the moment as getting married in a few months too.

Mike

[cjpacitto]

Oh, that's an easy one.... don't get married and you'll have plenty of money to spend on the car! (-:

[minho78]

Originally Posted by cjpacitto

Oh, that's an easy one.... don't get married and you'll have plenty of money to spend on the car! (-:

Absolutly. And once kids come along, you are constantly broke.LOL

[MrTibbs]

LOL.
She already calls the Porsche 'the other woman'.

I'm hoping to eventually set up a small business working 1 or 2 days a week restoring cars which will hopefully offset some of the costs of owning old cars. Luckily my current job's quite flexible in terms of reducing hours. The trick will be not just working on my own ones of course.