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Cylinder Scoring in 1500. Wondering how to continue

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dwhite10 Avatar
dwhite10 Dallas White
Edmonton, AB, Canada   CAN
Hello, I've had my 1958 mga for a few years now, but I had to store it 2 hours away due to space constraints. I've now got a garage for it and so I've started tinkering with all of the little issues it's had over the past few years. I had a major oil pressure issue as well as a clutch issue, so I pulled the engine out and have gotten I to diagnosing. I've arrived to the point where I will be doing bottom end bearings, machined crank, new cam, oil pump and associated parts. I was hoping to not have to do a full engine rebuild until a couple of years from now when I'll be in a better position to pay for it. The issue I've run across is there appears to be some scoring on the cylinder walls (see attached photos). The scoring is very light in depth (I can just barely, maybe not even feel it with my finger nail) but does appear on all cylinders. Since I don't have the budget now to do a full rebuild, I was wondering what my risk would be to do the planned work I had mentionned, then a couple years from now do the rest of the engine build. The car has light use and only in the summers, so I don't expect to put a lot of miles on it until the full rebuild. The car was not burning oil and had good compression before I pulled the engine. I want to avoid catastrophic damage and avoid damaging the new cam and polished crank. Do you think I'm OK to proceed without doing pistons and honing or is it too much of a risk? I haven't had to pull the head yet and would like to keep it on since it seems to be sealing well at the moment.

Also, I've heard if a product called Restorer that is an oil additive that's supposed to help manage blowby in high mileage engines. What are your thoughts on using something like this until I can do the full rebuild?

Thanks in advance for any help.

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bobs77vet Avatar
bobs77vet bob K.
northern Va, VA, USA   USA
just swap the bearings and ignore the rest if the engine was running well before.....dont skimp on the oil pump or timing chain and tensioner....

that scoring is pretty light and it also looks like its from below the rings, i dont think its a critical event. i wouldnt get too upset about it. the reality is these cars will last a long time and run with really poor internal conditions.

did you pull the head? if so what does it look like up top?

oil additives wont fix scoring. the scoring will only make you lose compression, contaminate the sump oil and burn oil, if the scoring is above the rings, so if it ran well before,,,swap the bearings and save the $$$ for a real rebuild

Edited 1 time(s). Last edit at 2017-04-20 08:17 PM by bobs77vet.

dwhite10 Avatar
dwhite10 Dallas White
Edmonton, AB, Canada   CAN
Ok, that eases my worry some. I haven't pulled the head. It's been sealing well so I figured I wouldn't mess with it if I didn't have to.

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Tbird Avatar
Tbird ET Taylor
Land O Sky, NC, USA   USA
Probably best with the new crank cam and bearings to just go ahead with the full rebuild now.

If the funds are just not there I think I would still pull the head and pistons.
Have the cyls honed and install new rings.
That would probably only cost an additional $150 ish parts and labor since it looks like you are doing the work yourself (unless you have a honing tool or want to rent one).
Might save the cyl walls from getting so bad that they will need to be sleeved at the time of the full rebuild.

Did something similar about 4 years ago. I re-sealed an engine and replaced the head gasket. Had about 200K on it. Just used a big flat file to clean up the block (studs removed) and head then put the new head gasket on. It's now using about 1 Qt of oil every 3-400 miles but he got 4 fun years out of it.

Interested to see what others have to say.


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RJBrown Avatar
RJBrown Randy Brown
Queen Creek, AZ, USA   USA
Very minor scoring. Ignore. Hone and Rings if possible. If you can't catch a finger nail on it it won't hurt to leave for now.
I had a Sentra that overheated and would not run. 1 piston was melted to the cylinder wall. Relative had no money. Chipped off the melted aluminum from the cylinder wall honed it and replaced all rings and one piston. Smoked like crazy for about 2000 miles. Quit smoking once the rings finally sealed. Car ran for over 100,000 more miles before it was sold off.

dipstick Avatar
dipstick Kenny Snyder
La Center, WA, USA   USA
1941 Ford N-Series
1958 MG MGA 1500 Coupe "Rosie"
1970 MG MGB GT "Pat's GT"
1971 MG MGB "Gifted To Me"    & more
"Very minor scoring. Ignore."

X2 Ignore the scoring.

- After camshaft break-in oil (30w non-detergent) is out, pour 1/2 can of SeaFoam into the oil, and the other 1/2 into the fuel tank. The SeaFoam will clean out the varnish, free up the rings, and clean the fuel system.

Be safe out there.

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Orting, Wa, USA   USA
I agree with others. If the scoring isn't too bad, hone (use a ball hone) and new rings. The extra cost for both would be less than $100.

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abowie Avatar
abowie Andrew Bowie
Adelaide, SA, Australia   AUS
1961 MG MGA 1600
1967 Jaguar E-Type "Rob's Car"
Leave it alone. It'll be fine.

Andrew B, Adelaide SA
MGA 1600 and some Jaaaaags

Mitchman2 Avatar
Mitchman2 Mitchell Andrus
Mills River, NC, USA   USA
If it doesn't catch your fingernail, leave it alone.

Buy a man a plane ticket and he flies for a day,
push a man out of an airplane and he'll fly for the rest of his life.

'30 Model A Ford
'48 MGTC
'58 MGA
'58 MGA

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