Old Corolla cyl.head.re-cond?

[LEVIS531]

I've an old C-reg 1.3 Corolla (220,000km, 1296cc, 12v, 2E petrol engine, 5 speed), rusting away but mech. in good shape (replace, repair all me own stuff). As I live in Germany and 160km/h is slow, I tax the old Jap girl a lot (I drive >30 000k /yr >90% Autonbahn@160). I bought the car a few years ago with genuine <50 000 km!. Compression finally went in no.4 cyl. Because compr. was pretty good in all other three, I guessed it was a bad valve. I have no garage/workshop/drive and always have to do all repairs on the street. I’d never done (and thought it was a “workshop job” to do) a cyl. head “rebuild” so I searched and luckily found a scrappy who’d just got writeoff same model 1.3 Corolla (automatic, but otherwise identical, “only” 170,000 km), and bought the engine, delivered, literally on my doorstep for 300 Euros. Although I’d swapped two engines before in my life (lived in rural US then which is paradise for car repair, if not politics!), I couldn’t find a tool hire centre here near my house for an engine lifter/crane and even if I had, I didn’t fancy rolling the thing around on the public street (German police, know what I mean?). So I just figured I would just use the head from the “donor” engine, “waste” the rest of the 300 euros worth, and swap the heads straight over.
Well, since separating both blocks/heads and disposing of my old head and the block from the donor engine (it’s criminal!! think of the parts source I threw out!! – but I have no cellar and the wife…..), I was away for a few months, in the US and a few people suggested I do a “poor man’s” head re-conditioning. I brought back a valve spring compressor and the sucker cups thingy + grinding paste (for in place valve grinding!). The “donor” cyl.head I guess is in good shape; I judge that the valves never saw the heat that mine did, by the “newness” of the exhaust manifold and carb/intake manif. (the scrappy was lazy and left all those on the engine plus other bits….yes!!), and being an automatic, the total revs would have lower and was likely driven some careful old kraut codger.
So the questions:


Should I just keep to plan A, and throw the “donor” cyl.head on my block, doing nothing to the head?

OR….

If I do the “poor man’s” valve regrind, should I replace the valve springs too?? (I need to spend some [cash Eur 30] on the 12 valve stem seals anyway). The Haynes says YES, if >70 000k. This is ca. Eur 50 from the Toyota dealer.

FINALLY…

Could all this be in vain? Is it possible that the original absence of compression IS a buggered piston ring on the no.4 piston and not related to the valves?? How can I check this? (remember, my orig. cyl. head is now discarded and I was too ignorant then to know to look specifically for a buggered valve – although…there was conspicuous uncombusted petrol residue (and no engine oil) all over the inside of the no.4 cylinder when I first separated the head - this is good evidence for a stuck open exhaust valve and not a damaged piston ring, no?)

My inclination is to press-on with doing the “poor man’s” valve regrind and go for springs. I enjoy messing with the engine and I probably will enjoy the re-newed horsepower (until the car rusts apart in a few more years).

I really appreciate any answers (and who said mid-eighties Jap cars were boring to drive?)

Chris

[tuttle]

Phew! big post

I'm inclined to agree with your 'poormans' approach(tho,tbh,I've not personally been inside a corrolla gl lump).Replacing springs on an hi-miler or kms in your case! engine of would be very desireable,esp as you have it all out & open anyway.You can loose compression thru damaged piston rings too,worth a check.
One thing did strike me.Matching the new cyl head,surely some careful skimming is going to be needed to get a good seal between new & old?
Best of luck.

[LEVIS531]

Tuttle, I appreciate the reply.

You say:
"Matching the new cyl head,surely some careful skimming is going to be needed to get a good seal between new & old?"

This worries me. I take it you mean checking for warping and taking the head surface down to exactly flat on both the block and head?? What is the difference between skimming and grinding?? Toyota spec is 0.05mm max. surf distortion. I'm re-joining with OE Toyota cyl.head gasket. I guess this I need to get a workshop to do this? There must be a limit that can be taken off (1.0 mm?) as then the valves are too near the pistonheads and compression is too high (premature detonation...)


Also:
"You can loose compression thru damaged piston rings too,worth a check"

How can I do this at this point (head/block separated?)

Thanks again
(and anyone else with comments)

Chris

PS I'll try to make my posts smaller next time. And by all means ask me anything about German roads, rules, etc.

[tuttle]

I'd strongly reccomend getting a shop to do the head grinding/skimming.It's not usually too £££ & you can just take the head along.Be v. careful when you remove it.
If pre-det is worrying you(due to the skim-which unless seriously warped will be v. minimal, >0.5mm is norm).You can help lower compression with a slightly thicker steel head gasket.Its a workaround/mod that some of turbo users do to help run higher levels of boost & minimalise pre-det.