I think im in deep crap now...during the rebuild my buddy cleaned off all the permanent marker labels on the pistons with brake cleaner now i only can tell Pistons 1,2,4. Is there a way to tell the configuration of 3,5,and 6. Please help!
Pistons have been mixed up during rebuild!!!
- Thread starter supersupramk3
- Start date
1. Never clean parts without being organized before cleaning
2. Never work with a friend unless yall have a system discussed before hand
3. Clean one thing at a time and put it down back in order in which it is to be installed
4. Scribe the order # in the bottom of piston in the meaty area around wrist pin
5. You are not fucked...take the block and pistons back to the machine shop and he can od mic the pistons and id "bore" mic the cylinders and relable the last 3 pistons.
DO NOT MIX UP PISTON RINGS!!!! that is the most important part...more important that mixing pistons as they are generally within .001 and will all work ok even switched but it's the rings that mean business
2. Never work with a friend unless yall have a system discussed before hand
3. Clean one thing at a time and put it down back in order in which it is to be installed
4. Scribe the order # in the bottom of piston in the meaty area around wrist pin
5. You are not fucked...take the block and pistons back to the machine shop and he can od mic the pistons and id "bore" mic the cylinders and relable the last 3 pistons.
DO NOT MIX UP PISTON RINGS!!!! that is the most important part...more important that mixing pistons as they are generally within .001 and will all work ok even switched but it's the rings that mean business
Measure them and then measure the bores, then put the right ones in where they fit with the best clearance
gaboonviper85;1355527 said:
Thx for the info, I knew Bud Light and precision work dont mix and match. LOL
I dont know if this helps, but all the rings are new from driftmotion...on stock pistons and rods. Its actually the rod bearings that attach to the crank that i am concerned about.
if they are all stock size, and you have the old bearings matched to each rod still, you can see what bearing number you have, and look at the marks on the crank to figure out which rod went where
So I take it you havnt gap'd the rings yet? If so you need to gap them..don't just put them in! Bring the block and pistons to the shop and the machinist can determine where they go...then he can double check with the plastiguage to make sure the bearings are correct.
Like I said..you're not fucked...you are seriously inconvienced and don't let your friend near your shit as either he was drunk or didn't have the sense to keep shit in order! If these bearings are clevites then it won't matter as all the rod bearings should measure the same as they aren't select fit like stock Toyota.
Like I said..you're not fucked...you are seriously inconvienced and don't let your friend near your shit as either he was drunk or didn't have the sense to keep shit in order! If these bearings are clevites then it won't matter as all the rod bearings should measure the same as they aren't select fit like stock Toyota.
CyFi6;1355555 said:
I used this to kinda figure it out, Im not to sure on how to read the crank markings though. TSRM pg. em-70
Rod has a marking, crank has a marking for each rod journal. Add the two numbers together (one from the rod, one from the crank) and that should equal whatever number bearing you need to use on that journal.
gaboonviper85;1355574 said:
Basically I gapped them and put pistons 1,2,4 in then thats when I noticed the issue of all the marked pistons gone. I am reusing the old rod bearings and am pretty sure they are the stock toyota.
Ummm...why would you re-use the bearings?
Did you get the rod big ends checked for roundness?
Did you get the crank journals checked?
If you are re-using the oil pump, I highly suggest you check it's clearances.
Don't be cheap or you WILL regret it.
Did you get the rod big ends checked for roundness?
Did you get the crank journals checked?
If you are re-using the oil pump, I highly suggest you check it's clearances.
Don't be cheap or you WILL regret it.
suprahero;1355597 said:
Well fellaz this is my first rebuild ever, i am very new to the "internals" world of engines. I dont have oodles to spend on the motor, so honestly is it that bad to reuse the old bearings. Bearings have not been mismatched with the rods, I just dont know which piston/rod set goes into which cylinder. I apologize if I ask dumb questions to guyz who know this stuff by heart. But thats why I am here for help in a supra forum.
Dude - if you don't do this correctly, you'll be doing it again...or, we'll get to see another Supra parted out. If $$$ is such a big deal, you don't need to be attempting this.
A block rebuild needs to be very precise...all clearances checked to spec. You don't want to reuse bearings any more than you would reuse rings. Bearing clearances depend on 3 things:
1) Crank journal diameter and roundness
2) Rod end -or- main saddle/cap diameter and roundness
3) Thickness of the rod/main bearings.
All have to be correct...once you disassemble, all need to be check and corrected if out of spec. That is if you want the motor to last any length of time.
In addition to ring gap, piston to wall clearance needs to be checked as well a cylinder bore roundness. If good, the cylinders need to be honed at minimum before installing new rings.
If this is a turbo motor, I highly suggest you replace the oil squirter bolts too.
A block rebuild needs to be very precise...all clearances checked to spec. You don't want to reuse bearings any more than you would reuse rings. Bearing clearances depend on 3 things:
1) Crank journal diameter and roundness
2) Rod end -or- main saddle/cap diameter and roundness
3) Thickness of the rod/main bearings.
All have to be correct...once you disassemble, all need to be check and corrected if out of spec. That is if you want the motor to last any length of time.
In addition to ring gap, piston to wall clearance needs to be checked as well a cylinder bore roundness. If good, the cylinders need to be honed at minimum before installing new rings.
If this is a turbo motor, I highly suggest you replace the oil squirter bolts too.
It all started with a BHG then I needed to get the head resurfaced, after that I found out I needed the block resurfaced, then I needed a valve adjustment with new seals, and for the block to be resurfaced i needed to take everything out bare block so they dont charge me 400 dollars to disassemble/reassemble...now I needed to rehone the cylinders and get new piston rings, and while my oil pan is off, now I needed a new gasket...you guys get the point. Its frustrating b/c a head gasket job now has turned out to be way more than that. Also I have driven this car less than 2000 miles for the 2 years Ive owned it. And that sucks. It seems these MK3 spend more time on the lifts then they do on the streets. So when machine shops dissassemble and reassemble they dont use your old parts? (For the Resurface)????
Now you've discovered the down side to using a MHG...it triples the work. You will hear guys "get a MHG and some ARPs and you're good!"...not that simple if you want to do it right. Basically, once you decide to go with a MHG, you committed to a complete rebuild. It's a bit late now, but you could have used a OEM HG and avoided all this.
You don't use a gasket for the oil pan...use Toyota FIPG or I like Permatex The Right Stuff.
The good news is you will have a nice fresh motor. Make sure you read the break-in thread in the Lube section
You don't use a gasket for the oil pan...use Toyota FIPG or I like Permatex The Right Stuff.
The good news is you will have a nice fresh motor. Make sure you read the break-in thread in the Lube section