EA81 Overhaul thread

steptoe · Post by **steptoe** » Thu Jun 09, 2011 9:01 am

oil filler tube gasket, the oil pump gasket kit is a genuine thing really - about $20 for the o rings and gasket , al available individually

littlewhiteute · Post by **littlewhiteute** » Thu Jun 09, 2011 8:05 pm

steptoe wrote:Before fitting rings to pistons it is always advisable to fit each ring to the bore and measure the gap and note it, slide ring down bore and measure gap there. There is a formula based in bore diameter in inches and how many thou gap is acceptable. Too tight means using a file to remove a bit off the ends of the ring. Always best to check.

Correct, rule of thumb is .003 - .005 per inch of bore.

Silverbullet · Post by **Silverbullet** » Thu Jun 09, 2011 8:12 pm

Got it! Thanks

steptoe · Post by **steptoe** » Thu Jun 09, 2011 10:14 pm

as a minimum gap

Silverbullet · Post by **Silverbullet** » Fri Jun 10, 2011 6:38 pm

Well that was an interesting two days!

The block and crank were supposed to go yesterday, dad was going to take them while I was at tafe. He didn't, he wasn't sure if I wanted to leave all the bolts and studs in where they were

(I left them in so I knew where they went) but I said it's fine.
So he took the bits today while I was away, I was expecting to get them back next week maybe at the earliest. Nope, everything was ready when I got home!

Even the bearings, rings and gaskets! All the gaskets I need plus O rings and even things I didn't think of in a single kit. You know those plugs for access to the gudgeon pins? they have aluminium washers which were in the kit, as well as the filler tube gasket and pickup tube O ring

And to think, this little engine shop had all this in stock ready to go! I had to wonder when the last time they needed a bearing set for an EA81 was

The shop also checked my bearing oil clearances for me, so I don't need to bugger around with that plastigauge stuff:p

Anyway, got everything I need and more back the same day, for less than I was expecting ($320 all up) I'm pretty chuffed. Now on to taking the heads apart, pics soon.

Oh and just thought I'd apologize to our forum parts guy frog (if you're reading hehe) for not getting the parts through you, but it was just so easy to get everything from the one place, hope you understand

Cheers!

littlewhiteute · Post by **littlewhiteute** » Sat Jun 11, 2011 8:36 am

littlewhiteute wrote:Correct, rule of thumb is .003 - .005 per inch of bore.

steptoe wrote:as a minimum gap

I wouldn't class it as the minimum gap, more considered acceptable range.

Eg: I wouldn't run a .020 gap on a 4 inch bore.

Silverbullet · Post by **Silverbullet** » Sat Jun 11, 2011 2:20 pm

Got around to disassembling the 1 and 3 side cylinder head today, I found a place to put the two halves of the block while I did the cylinder head and got to work. Everything came apart with no troubles, and of course, absolutely no damage anywhere

Some pics

Re installing keepers

Valve reassembled

steptoe · Post by **steptoe** » Sun Jun 12, 2011 3:56 am

mystery continues.....

littlewhiteute · Post by **littlewhiteute** » Sun Jun 12, 2011 7:56 am

Make sure to deburr the sharp edge from the combustion chamber.

steptoe · Post by **steptoe** » Sun Jun 12, 2011 12:51 pm

why ?

Silverbullet · Post by **Silverbullet** » Sun Jun 12, 2011 5:15 pm

Progress progress...

After all my fruitless searching and head scratching, today I just thought Bugger it I'm putting this thing back together noise or no noise. Since there is obviously nothing wrong with the big end and crank side of things and there's nothing wrong with the head, the only other things it could be are things that I can fix with the engine in the car (if it still makes the noise when I put it back...if it still works when I put it back

) So I've started reassembling, if I regret this decision then so be it!

First was cleaning the honing oil and crud off of the block and bores. I followed the machine shops directions and used hot soapy water in a tub and sure it cleaned everything off, but then the water picked it up and coated the bores in it

So I spent another while cleaning the grit out of the bores with solvent and then a light coat of oil to prevent rust. Thankfully the crankshaft was alot easier, just a clean solvent soaked rag and it was spotless.

So here are pics of todays progress on the rebuild: Got all the rods back on and the crankshaft is ready to go back in (yes I lubed the bearings before I put it back together). Tonight I will check the piston ring end gaps and get the pistons ready so they are good to go when I need them. Hopefully Crankcases rejoined tomorrow!

Bores cleaned and ready, gladwrap seals in freshness! ...and keeps dust out

Cleaned crankshaft and No. 1 rod

Mmm new bearings!

All rods on and bolts torqued

YouTube · Post by **El_Freddo** » Sun Jun 12, 2011 5:24 pm

Looking good there silverbullet!

Should go well once its back together! I was hoping that you would go for the cam grind - each to their own I guess.

Cheers

Bennie

littlewhiteute · Post by **littlewhiteute** » Sun Jun 12, 2011 5:28 pm

littlewhiteute wrote:Make sure to deburr the sharp edge from the combustion chamber.

steptoe wrote:why ?

Sharp edges run hotter, the chamber will then be more prone to preignition.

littlewhiteute · Post by **littlewhiteute** » Sun Jun 12, 2011 5:32 pm

Silverbullet,

Did you check bearing crush?

Do you know how to time your camshaft?

Do you understand the importance of the engine has to fire first go and run for 15-20 minutes at 2000+ rpm to run-in the cam?

Silverbullet · Post by **Silverbullet** » Sun Jun 12, 2011 8:14 pm

littlewhiteute wrote:Silverbullet,

Did you check bearing crush?

Do you know how to time your camshaft?

Do you understand the importance of the engine has to fire first go and run for 15-20 minutes at 2000+ rpm to run-in the cam?

Do you mean bearing oil clearance? Short answer, No. Because when I asked the the machinist at the engine shop if they had or knew where I could get plastigauge to check the oil clearance, he said they don't stock it and don't trust it anyway. I had my crankshaft linished/polished and they measured the journals and the bearings to find the oil clearance so I'm going on without measuring. This may prove a big mistake but we will see.

For timing the cam there is a single punch mark on one of the gear teeth which I have to line up with a certain hole in the crankshaft right? And I didn't get my cam reground in the end, do I still need to run it in as you describe?

Cheers!

littlewhiteute · Post by **littlewhiteute** » Mon Jun 13, 2011 5:31 am

Silverbullet wrote:Do you mean bearing oil clearance? Short answer, No. Because when I asked the the machinist at the engine shop if they had or knew where I could get plastigauge to check the oil clearance, he said they don't stock it and don't trust it anyway. I had my crankshaft linished/polished and they measured the journals and the bearings to find the oil clearance so I'm going on without measuring. This may prove a big mistake but we will see.

For timing the cam there is a single punch mark on one of the gear teeth which I have to line up with a certain hole in the crankshaft right? And I didn't get my cam reground in the end, do I still need to run it in as you describe?

Cheers!

Bearing crush is what holds the bearing in the bore. Eg: big end bearing fitted to rod, one bolt tensioned up and the other slightly loose, there should be a gap around .002 - .006 between the parting faces of the rod.
This gives the interference fit within the rod to hold the bearing. If you're happy with the shops measuring, you should be fine, do they feel ok after assembly?

If the lifters were kept in order AND the base of the lifters and cam lobes have normal wear patterns, you won't need to do a run-in procedure.

If the lifters got mixed up, or any doubt, get them radius ground.

I would still apply an engine assembly lube to the cam lobes/lifter bases as a precaution, part of normal practice.

Dot on camshaft gear visible through the one different flywheel bolt hole, (chamfered).

steptoe · Post by **steptoe** » Mon Jun 13, 2011 10:41 am

Sam is doing well, well read, well prepared, speaking of which - got the Loctite grey maxx for sealing two block halves together? It is what I used twice now. The EA81 cam is fol proof eh? I once fitted a bearing cap around the rong way and was it tight? Do a double check as you assemble with a silent observer - no crack beers until it is at least together.

Glad wrap is good, but a um, lets just call him an experienced smarty pants son of a car genius, warned me plastic does not breathe so moisture can stay in with your bare metal - can't win can you ?
Keep up the good work and story

Have never used plastigauge - always trusted machine shops. Gotta trust one that does not even stock it let alone use it. They trust the bearings the sold you, I would too

Silverbullet · Post by **Silverbullet** » Mon Jun 13, 2011 12:12 pm

littlewhiteute, Ah I see, when you said bearing crush I just thought crushed plastigauge

I haven't heard about bearing crush yet, is there something I need to be aware of? If it's relevant I tightened up the big end cap bolts evenly and worked up to the torque in 3 steps. All of the rods rotate freely and smoothly with no binding on the crank, feels about the same as before I took it apart.
Also I have the individual lifters in separate labeled bags so there's no mix up. With all the engine parts in separate bags I've got a mountain of plastic on the bench

steptoe, Thanks for the tip I wasn't sure of what to use for the crankcases. Looks like I won't be putting the halves together today anyway; thinking I've strained a ligament in my shoulder or something, can't use my entire arm!

Certainly won't be lifting block halves and torque-ing up bolts. Will give me time to get the loctite. There's no chance I put the caps on the wrong way either; before I took them apart I put tiny corresponding centre punch dots on each rod and cap on 1 side only, lined all those up again on reassembly. Makes sense about the gladwrap too, it's gone now.

As for being well read, I can thank the workshop manual for that! Pretty much my bible

steptoe · Post by **steptoe** » Mon Jun 13, 2011 1:54 pm

It is loctite brand but a fine as in small silicone like goo. Got some as recommended by the loctite chart for this job, whereas my machine shop fella says loctite aviation #2 never set hard goo is his choice

littlewhiteute · Post by **littlewhiteute** » Mon Jun 13, 2011 2:13 pm

Silverbullet wrote:littlewhiteute, Ah I see, when you said bearing crush I just thought crushed plastigauge I haven't heard about bearing crush yet, is there something I need to be aware of? If it's relevant I tightened up the big end cap bolts evenly and worked up to the torque in 3 steps. All of the rods rotate freely and smoothly with no binding on the crank, feels about the same as before I took it apart.
Also I have the individual lifters in separate labeled bags so there's no mix up. With all the engine parts in separate bags I've got a mountain of plastic on the bench

steptoe, Thanks for the tip I wasn't sure of what to use for the crankcases. Looks like I won't be putting the halves together today anyway; thinking I've strained a ligament in my shoulder or something, can't use my entire arm! Certainly won't be lifting block halves and torque-ing up bolts. Will give me time to get the loctite. There's no chance I put the caps on the wrong way either; before I took them apart I put tiny corresponding centre punch dots on each rod and cap on 1 side only, lined all those up again on reassembly. Makes sense about the gladwrap too, it's gone now.

As for being well read, I can thank the workshop manual for that! Pretty much my bible

You can still check bearing crush, undo one conrod bolt and you'll see a gap emerge.
I've dealt with an engine shop that didn't understand this theory, I don't deal with them anymore.