Toyota Celica Supra Forum banner

1 - 9 of 9 Posts

·
Registered
Joined
·
51 Posts
Discussion Starter #1 (Edited)
I'm trying to find a more reasonable price on Toyota main bearings for my 90 7mgte Supra.
The first place I called didn't know what i was talking about "are they pulley looking things?":eekfacepalm:
Second could only find .25 under in a set for $350.:ugh:
Third place at least found them, so they are available. The $37-$39 per main is more than I want to spend though.
Looking for a wide #3 a narrow #3 and #2 x5
Thanks
 

·
Registered
Joined
·
51 Posts
Discussion Starter #3
I have some clevite (ndc) in standard and the clearance is near the max but one is .0030". I have some Taiho bearings in STD that were for another engine I think I'll try and just order the few thicker stock ones I'll need.
One thing I'm not sure off is how does one distinguish the the one wider bearing from the other narrower ones when ordering?
 

·
Premium Member
Joined
·
3,656 Posts
Toyota distinguished the front main bearing shell from the others in the prefix of the part number (11701 and 11071). The mark sizes (last two numbers in the part number) indicate 5 different standard measurements in .00015 increments...meaning the engines were basically blueprinted from the factory. Just order a standard set of main bearings from a reputable aftermarket bearing manufacturer and you should be fine as long as the crank journals measure out to spec. I can't get all the mark sizes any longer and usually just order a standard set from Toyota. The front main bearing is wider, not thicker, and it's location tab is on the opposite side of the shell. The rod bearings are all the same.
 

·
Registered
Joined
·
51 Posts
Discussion Starter #5 (Edited)
Thanks for that info. The issue I'm having is that the machine shop did not listen to me when I said I wanted the bearing clearances around the middle of Toyota recommended spec. My goal at the time was 500hp, so I think they either just left clearance's loose (they mainly did domestic's) or just ignored what I was asking for because they were very backed up with work due to an injured worker and being 1 of only 2 machine shop's in the city.

I borrowed some tools at the machine shop where I was working at the time, and checked the rods/mains. Rods were all .0015" (new eagle rods) and most of the mains were outside factory spec, 3 being .0028" and 1 @ .0030". This was with STD Clevite rod/main bearings.

I'm in a new city and found another machine shop. I had them install the oil pump shaft bearings (old shop left diamond shape dents in the front bearing) I also had them check the mains were straight with the ARP studs and double check clearances. What I got from them was "mains are straight, crank is a little under but the mains on the block are tight".
They didn't get give me any measurements but it doesn't matter anyway, when I got the block back the mains were installed 7-1 from Front to back:censored:

I have a set of STD Taiho bearings I will try, my hope now is that I can just order the Toyota numbered bearings to tighten up the clearances on the loose mains. Maybe I'm being too anal about this.

Are the Toyota numbered bearings made by Taiho? Every time I've ordered bearings from Toyota they were a Taiho bearing.

^^that's a longer post than I was intending, thanks for your help and your time.
 

·
Premium Member
Joined
·
3,656 Posts
The Toyota sizes are .00015 (1.5 ten thousandths) apart from each other...you're not going to get your clearance even with the thickest bearing shell. Sounds like you need a new crank or have yours machined (.010) to accept the undersized main bearings available in the aftermarket. And no...you're not being to anal about this at all...bearing clearances have a direct effect on oil pressure...tighter the clearance...more pressure.
 

·
Registered
Joined
·
51 Posts
Discussion Starter #7
I wasn't thinking just how close the Toyota bearings were. Sounds like I need to get a bearing mic and start measuring the bearings I've got. If I'm lucky I can use the 2 thickest shells I have or you can still get the #5 shells, and they're thicker than the std shells I already have (yeah right) and I can use those.
The difference between the #3 that were the originals #5 is .0002"-.0004" x2 for each shell is .0004"-.0008"
All I need is to find .0002" on the one main that's beyond The tsrm .00028" max. I didn't think I was going to get within the factory spec, and wasn't expecting too.
I know this sounds like alot of pissing around, but I've already paid to have the block decked, oil pump shaft bearings installed and the crank and mains checked TWICE, because mistakes/quality of work from the first shop.

I'm not paying to have the crank ground for another set of U/S bearings (I was more than willing the first time) AND pay another $275 to have everything balanced again.
Anyway, thanks again, I know this is supposed to be a vendor section.

I just remembered, someone on supramiana used that DIY techline coating on their bearings and it also iclosed up clearances a small amount... Hmmmm? I think it was Adjuster? ...I got some more searching to do:rolleyes:
 

·
Premium Member
Joined
·
3,656 Posts
Ok...you posted the first time in thousandths (.0028 and .0030) and the second time in ten-thousandths (.00028 and .00030)...there's a huge difference between the two bro and I think you're confusing them. Standard oil clearances are .0013 to .0023 in the TSRM...anything tighter and you run the risk of metal to metal contact because there's not enough clearance to get oil in between the two surfaces once the metal expands. The shell differences are in ten-thousandths...and you need to make up a thousandth (.001) to get the main line tight. Coatings are not the answer...they don't take up the slack for what should be metal and they expand and contract at a different rate than the surfaces they are mated to. It'll just prematurely wear...especially so on a Turbo engine (heat). You can do what you want I guess...but a new crank with good main journals is the only 'correct' answer in my book. DIY coatings...yikes! Assuming your journals are symmetrical, your x2 math is incorrect...the clearance will be the same on both sides yes...but you don't add them together to get your clearance. Now...looking at the TSRM...they list an undersize bearing shell for the mains at .050...THAT'S what you need to tighten up the clearance on your crank but again it would require grinding the crank. I'm not sure they are available anymore...but it would be worth looking into.
 

·
Registered
Joined
·
51 Posts
Discussion Starter #9 (Edited)
:duh: confuse the two? Perhaps I did. As for the clearance, what I had in my head was.
Measure the block mains without bearings
Measure the crank mains
Measure bearing thickness X 2 (for each shell)
The difference between crankshaft and main housing diameters and double shell measurement is whats left for clearance.

I any case you're correct, I'm not going to get things tight, short of grinding the crank.:32:
I'm putting the running 7m from my parts car that was to be for the Celica into my Supra and enjoy cruising during our very short summer...I'll come back to this engine later.

Edit:

All I need is to find .0002" on the one main that's beyond The tsrm .00028 max
This is the mistake in my previous post it should read .0028" max. The only main that is beyond the tsrm max is .0030. I only want to get within Toyota's recommended maximum not the standard clearance, if that's what you're thinking.
 
1 - 9 of 9 Posts
Top