Very low compression
 

i recently bought a 89' turbo and i ran a compression test to find out why its smoking. no. 1 cylinder has 50 psi while the rest are within spec. I poured some oil in no.1 and it jumped to 70 psi so im pretty sure its a bad piston ring. So i was just wondering what are my options. How hard is it to change piston rings myself or how much would a mechanic charge. Also would it just be cheaper to buy a new engine? I can get one for about 1k.

Could be a BHG. Have you checked?

Doing the piston ring by your self (I am considering that you have a little mechanical background) sucks. I rebuild a n/a 7m a long time ago and there is no easy way to do just that. If you can get a new motor for 1k I would say shop around because I have seen 7mge for like 500 and 7mgte for like 750 to 900. Just remember if you go the new motor route check the HG and possibly replace it with the motor out to save you some headache down the road. You dont know how that crazy Japanese guy treated that motor or whoever you get it from. But in the mean time seeing as you will have to pull the head anyways then pull it. Check the valves first oil will make them seal up a bit as well usually they will go before the rings do most of the time and they are easier and cheaper to fix. Also check the head gasket if it is bad change it you can drop the pan just enough to break the rod bolts on number one then just push it out the top and inspect it. Sad thing is you cant just buy the rings for one piston they come as a set and if you went this far might as well hone and replace them all. Well I think I have exausted myself and your eyes OH YEAH if it is a 7mge you want parts to I have one sitting that has good rings and vlaves.

Thanks for the advice. I'm changing the head gasket right now and i cant seem to reach the bolts for the turbo oil line. i have everything off except the turbo and ex. manifold. anyone know how to remove the turbo?

Those bolts are real tough. I ended up cutting the lines off, and then had to buy a good used set. I'll see if I have any photos.

20 psi is just around specs for the jump in psi with a wet test. Even brand new motors will jump considerably in compression when doing a wet test. I wouldn't say your rings are bad. Try a wet test in the other cylinders and see how much they jump up.

Alright i got it off finally but i had to use a special tool.
http://i27.photobucket.com/albums/c1...n/IMG_1281.jpg
I was also wondering if this is the stock fuel rail.
http://i27.photobucket.com/albums/c1...n/IMG_1289.jpg
might as well post the progress
http://i27.photobucket.com/albums/c1...n/IMG_1282.jpg

What type of socket do i need for arp head bolts?

The head already has arp bolts/studs whatever the difference is.i dont have a socket that will remove them.
btw, i already have this
http://i27.photobucket.com/albums/c1...n/IMG_1258.jpg

???

Bolts have heads on them, while studs do not. You use nuts on the top of studs.

I could have made clearance for the ARP bolts, but I didn't want to do any grinding while the head was on, and I sure wasn't going to pull it back off. So I just reused the stock head bolts.

I believe so... The rail on my N/A looks nearly identical

Well its off now. Do you guys think these scratches will be a problem with the new hg.
http://i27.photobucket.com/albums/c1...n/IMG_1298.jpg

That should be resurfaced! Those "minor erosion cuts" are in the worst possible direction--a sure future leak path.

Damn, i was hoping it wouldnt be that bad. Whats a good place to get it resurfaced for cheap?

Finally put it back together. put a new head gasket and water pump just because. but its putting out even more smoke than before. when i got the head back from the machinist it had ridges the whole way across the surface. was it supposed to be like that? also its shooting out smoke from the pcv and theres a lot of pressure in the valve covers.am i going to have to take it apart again and have the head reresurfaced? did i not torque it right, i put it to 75 ft/lbs.
this sucks ass

The head will not slide down to the head with the studs inserted.
You have to drop it onto the guidpins and then install the washers and then the studs or you'll be pulling the head off and on till you do it the right way.

Whoa, 50psi on #1 and only 70 wet? So have you replaced the rings or not? Is your dipstick getting blown out yet?

:gotnos: Pardon the pun.

I'd lap that block at home. If that's the worst damage you have.
Mine was much much worse.

I didn't have a problem lining up the head i just put it on and dropped the bolts in the holes.
the block is smooth i dont think thats the problem. i havent changed the rings. the seller told me it was a low mileage engine that he swapped in so i doubt its the rings.i also noticed white stuff on the oil cap but that could just be this grease that the machinist put on the lobes and lifters when i got the head back. i have the pcv rerouted to a catch can and then to the atmosphere and theres white smoke coming out of the pcv lines.how can there be smoke. there wasnt any before. can all this be explained by a badly resurfaced head?

Sigh... I'm sure it was a low mile JDM engine.... and God only knows how hard it was beat on before it came to the states and then how long it sat in a shipyard with a gentle mist of surface rust slowly leaving little pock marks of love everywhere important.

Seriously... how many JDM engines have you seen? Half of them were driven to the point that they could no longer pass inspection (often without oil) and then simply discarded for something newer.

White smoke? Does it smell sweet? White grease? Sorry, lithium grease isn't really used as an assembly lube... you're probably looking at an oiling system full of coolant. Have you checked the radiator for oil?

You know, the PCV system is actually VERY beneficial to older engines. It actually helps prevent blow-by. It creates suction which evacuates the blow-by gases which occur in all engines. get the breather off of it and run it to a vacuum source. If you don't like it running to the TB then run it to the exhaust. And if you're going to keep it running to atmosphere the catch can isn't going to do much more than sit there looking pretty.... well, in your case it's probably full of coolant and unburned fuel. :frown:

A light textured swirl pattern on the head and block deck is actually desireable if you're running an OEM type graphite HG. If you're running a steel HG you want smooth as glass and straight as hell. You need to specify what your doing or they'll assume it's a rebuild per specs. With the texture you should just barely be able to feel it with your fingernail.

Most shops will give the head a light soda blast to make it all smooth and like minded.

Are you serious? New one to me. I really can't imagine how that would serve any more purpose than cleaning off the rest of whatever carbon was still stuck to the valves so you think you're getting your money's worth.


BTW, you seen that they now make equipment for blasting with pulverized dry ice? No mess! Oh, and it's cold, so it's the safest thing to use on sheet metal!

Well in this neck of the woods they do and that's because the old napa parts store is the village machine chop main.

Well I've been procrastinating, but i am finally going to change out the piston rings. I read a post that said the oil pan can be dropped by just jacking up the engine a few inches http://www.toyota-supra.info/forums/...html#post32515.
Is there anything i should know about this method. Plus the head is already off so is it going to be a problem if i try to jack the engine from the motor mounts instead of the hooks on the head?
Also, are beck/arnley piston rings any good? I'm liking the $30 price tag from rockauto.com. Thanks in advance for any input.

help me out here people.

input: Take the engine out. Theres no point of leaving it in if everything is already apart, theres hardly anything keepin it in there! You are going to have a much higher chance of damaging expencive internal parts if you do it from the bottom, and you will likely end up with more issues than you started with. You should probably at least get the block honed out equally if measurements come out into spec.

PAULMICIN: You have got to stop using autozone parts on this car.

Those parts are bandaids and you are setting yourself up for more work.
Parts like those you should be going toyota oem from the dealer. Unless you're punching and stamping the block.

And then aftermarket. AutoZone is the DEVIL. :)

Ok, well I would get dealer rings if i could, but they are much too expensive. I found nippon piston rings for $48. doesn't nippon make oem spec?

as far as i know beck/arnley arent bad parts. But i dont know about rings.

I have heard alot more about nippon than beck and arnley or whatever that stuff is.

Check out: Performance Parts Aftermarket and Racing

See what these guys carry. Call them and dial ext 103.
Speak to Dave. If he can't find you some quality rings at a fair price.
He can point you to them.

O'rielly's is the lowest grade parts distributor I will use on the supra and I am so utterly choosey about not having to keep working on this tramp that I refuse to stoop to lower quallity parts..

Not that this has aided my car in running or anything but it should when I get it sorted out somewhere around 2010.

As far as lifting the engine a few inches, is there anything else that needs to be unbolted besides the engine mounts? is there anything holding the transmission down? thanks in advance

Please read the tsrm! There are other things, yes.

edit: thought you were removing the engine

So it turns out you cant lift the engine just enough to remove the oil pan, it needs more clearance than that. The tsrm states that you can just lower the crossmember with a jack and put it on 2 jack stands. what i want to know is, is the crossmember balanced from the center? or is it going to lean towards the back of the car when i try to lower it with a jack?

Hey look what i found!!!
http://i27.photobucket.com/albums/c1...n/HPIM1017.jpg
That aint no piston ring. damn crappy stock pistons. guess its time to get some nippon pistons.$100 for a set with new rings. not bad i think.sorry its not eagle, im not rich.
http://i27.photobucket.com/albums/c1...n/HPIM1018.jpg
http://i27.photobucket.com/albums/c1...n/HPIM1019.jpg
http://i27.photobucket.com/albums/c1...n/HPIM1020.jpg
http://i27.photobucket.com/albums/c1...n/HPIM1021.jpg

Nice find! lol. What does the block look like?

the cylinder walls are mirror smooth. lucky me i guess. There was much antifreeze in the oil pan and under all the rod bearings, but i am changing them out. I only drove it like 5 miles since i got it so there shouldnt be any damage to any major parts.

You should get someone to check out the block, might look okay on first glance but it could be scored and or be out of round/tapered.

True, that piston had to be rubbing on something....