Pull engine.

Remove head.

Remove pistons.

Purchase new rods.

Take block and crank to machine shop.

They will grind down the crankshaft journals to make it smooth again and then install larger bearings to compensate for the metal that was removed from the crank.

If you rebuild this engine or purchase a used engine, you're already going to need at least $1,500 depending on how mechanically inclined you are.


If you just lost you job. Then go ahead and give up because you'll never fix the car. So log out of Supraforums and start looking for a job.

 

They will grind down the crankshaft journals to make it smooth again and then install larger bearings to compensate for the metal that was removed from the crank.

No, they will install undersize (smaller) bearings since the crank journals were ground smaller.

 

your back, so soon?

 

You're*

 

sic burn, I got roasted...


edit: ya, sorry op... i'll cut it out now

so question time:
is it ge or gte?
your dd, or a weekend toy?
are your doing the work yourself?

 

Stop making this thread off topic. I'm trying to help OP. But your faggotry is making it rather difficult.

 

Just cuz he lost his job doesn't mean he has zero money...

To install pistons you have to drop them in from the top? Would it really be required to pull the head? I'm just wondering since I've never done it plus it might help OP

 

He said in his original post that he has no money.

Yes, pistons must be installed from the top in order to properly use a ring compressor. So pulling the head is a must.

Besides, the engine block has to be bare in order to be machined properly by the machine shop.

 

thought more about this driving home from work tonight...

swap in a 2jzge ill assume your turbo currently...
you need flywheel, bellhousing, correct oilpan, and motor mounts. keep the gte harness/ecu and cps. sell engine/turbo to offset 2j budget. stay na till you land a job and go from there. under a grand if you play your cards right buying parts. and youll be on the road sooner than rebuilding the 7m.

as much as I hate when ppl say "2j it" its your best shot to stay cheap and reliable... the 7m will not tolerate any shortcuts durring a build.

 

Even if you could compress the rings from the bottom you cant install the pistons from the bottom, the main webbing is in the way on every engine I have ever worked on.

 

One more thing to consider, I have heard that when rod bearings go bad or on any rebuild replacing rod bearings that the rods need to be reconditioned to make sure the rod bearing surface is exactly round/correct size . The rod takes quite a beating and can actually become out of round which will just ruin the new bearings you install.

Over sized bearings might not be needed. Only way to know is to get the crank to a good machinist and have measure it at different angles, then a polish or grind could be done. This would require a complete rebuild done of course.
If you are looking for a cheap quick fix and the crank rod journals are not scored you could just replace the bearings with stock size and put a upgraded oil pump from driftmotion to possibly increase oil pressue, it may or may not fix for a long while. If you can get the oil pan off with the engine in the car this would be possible, I have done it on a four cylinder car but the sub frame might be in the way on the supra. Otherwise the engine would still have to come out, same process though . Change one rod bearing at a time, use plenty of assembly lube, rotate the crank to get each rod accessable. After you remove each cap, put the rod stud protectors over the bolts before you push the rod up to remove the top half of the bearing so you don't scratch the crank. Check each journal first before installing new bearings though.

 

If your bearings went bad, you'd better clean everything inside the engine really really well. Every engine I've ever taken apart that had bad lower end bearings also had metal shavings all over everything, and the oil pump was usually messed up from those shavings. If there is metal in there don't forget to clean/check the turbo CHRA. Already seen new engines ruined from shit left in the turbo CHRA.

 

Thanks for all the advice guys, i guess im just going to pull out the engine and inspect it first before i do anything...
i ono if this matters but when idling, it doesnt knock at all it.. it only knocks when increasing rpms

 

Thanks for all the advice guys, i guess I'm just going to pull out the engine and inspect it first before i do anything...
i don't if this matters but when idling, it doesn't knock at all it.. it only knocks when increasing RPMs

Crazy idea, but double check to make sure your crank pulley isn't just loose.

The crank pulley on my 7M came loose once and it sounded like rod knock when the RPMs went up. A new bolt with alot of locktite fixed that problem.

 

if you hear the knock around 2800-3,200 rpm low in the engine .. you can safely "Assume" its rod knock.. If you want a quick fix.... get a nice new oil pump throw some clevites in thats about your best bet.. If you can't handle atleast that then its probably not worth yours/our time. if you really want to fix it right atleast save 2k for it for stock condition

 

if you hear the knock around 2800-3,200 rpm low in the engine .. you can safely "Assume" its rod knock.. If you want a quick fix.... get a nice new oil pump throw some clevites in thats about your best bet.. If you can't handle at least that then its probably not worth yours/our time. if you really want to fix it right at least save 2k for it for stock condition

I wouldn't call that a "quick fix". More like a waste of time and money. That should never be done to any engine.

 

he would spend so much money on that engine it's not worth spending Thousands of dollars on.. he's better off Following your build then.

 

Forgot to mention the cleaning. If there are shavings in the pan(hopefully very little) you need to clean it very well. Either have it vatted($15) or degrease it followed by blowing compressed air back and forth making sure to get all of the shavings out.

I recomend this oilpump http://store.driftmotion.com/static/i-driftmotion7m-gteupgradedoilpump.php

I think the reason the 7M gets rod knock alot of times is because of the low oil pressure at idle due to inadequate oil pumps from the factory. Of course these engines aren't exactly new but the JZ's don't have near as much problems with rod knock and oil pressure at idle with the JZ is very good.

 

I still think for the money availible and skill required to rebuild the 7m, the na 2j is a better option.

instead if going broke on machining cost, aquire a bellhousing, flywheel, starter, & motor mounts... your set, sell the 7m for scrap or make a coffee table out of it.

 

^^:bigok:^^

 

Actually, they are called "undersize" bearings because they are used on a crank shaft that is "undersize".

 

Thanks for stating the obvious? I was making a joke because degree said "larger" bearings, which is right in a way...

Degree is right again with you can have oversize and undersize bearings, although oversize is uncommon because they're generally used with control broken rods.

 

I think if you grind the crank, you need undersized.

If you machine the rods, you need oversized. Right?

















If you machine both, you need a 2JZ.

 

if you machine both, you need a 2jz.

lol