Why is that?
Motor tear-down and rebuild... Tear Down. (1 Viewer)
- Thread starter concretejungle
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Why is that?
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Alex is doing a bottom end rebuild as well IIRC, so the chain being supported or not is really of no consequence at this point.
Everything is coming off and out.
Everything is coming off and out.
- Thread starter
- #25
haha, no burnt pistons! Just a horrible knock which i "guess" could be called a loud tick... maybe a tick on steroids! I might end up giving Beno credit for it being a valve way out of adjustment.
Thanks J for posting those pics!
Yes, the plan is to pull the entire motor and have it bored over. Trying to decide on either Toyota bolts or those ARP studs that bjowett and landtank have used.....
Thanks J for posting those pics!
Yes, the plan is to pull the entire motor and have it bored over. Trying to decide on either Toyota bolts or those ARP studs that bjowett and landtank have used.....
If you are going to do an overbore Alex, I'd definitely talk with Robbie/Rick/Mike about using ARP studs. They're not plug and play. Also, the HG is going to have to be a Cometic HG as they are the only ones making overbore HG's for the 1FZ.
Lemme know when you need parts.
Lemme know when you need parts.
the responses to the screw drive comment is correct. You need to keep the cam sprocket in place to maintain timing. But since this is a full tear down it doesn't matter.
- Thread starter
- #28
That is correct. Should i not be rebuilding the lower end/block then i would have kept the timing chain in place.
Beno, I thought that Toyota sold oversized rings and HG? I did not know it would be a cometic HG. Yes, i do plan on using the ARP fasteners. I also know that two need to be ground.
I do plan on turboing this motor, so i would like to put it back together as bullet proof as possible.
We sell the pistons (1.0/.5mm over) and rings. As far as I know, Toyota does not have HG support for the overbore.
If you are going to turbo it, Cometic seems to be the only way to go.
I would advise you to source a good 11-mm x 1.25 pitch tap and die. These are not commonly found and chasing the tap into the block for the head studs/bolts is a very good idea and if you are grinding/cutting the two ARP studs the die is obviously helpful.
That also just brings up the point that having a good set of taps and dies for all the fastener sizes you'll be touching is great to have on hand. The exhaust manifold studs are another place where chasing the threads with the tap saves you headaches.
Also, pretty much the first thing Cometic will ask you is "How thick do you want it?" By their specs the OEM unit is ~52 or 53 thousandths thick. They can go from (I think, recalling from memory) 25 thousandths to 140 thousandths, with increments of 5 thousandths. Their turn around is less than a week so if you aren't in a hurry you can just wait until you know for certain how much was taken off your head and/or block and then compensate accordingly to at least get it close to the factory specs. My block surface was quite pitted and needed ~6-7 thousandths taken off and the head had ~8 thousandths taken off so the Cometic HG I used was 70 or 72 (can't remember for certain) thous thick.
Hope this is useful.
EDIT: My contact at Cometic was Chris Workman. He was very helpful and should know what you are talking about when you are requesting a 1FZ-FE HG that might be over-bored and want different thicknesses, etc.
That also just brings up the point that having a good set of taps and dies for all the fastener sizes you'll be touching is great to have on hand. The exhaust manifold studs are another place where chasing the threads with the tap saves you headaches.
Also, pretty much the first thing Cometic will ask you is "How thick do you want it?" By their specs the OEM unit is ~52 or 53 thousandths thick. They can go from (I think, recalling from memory) 25 thousandths to 140 thousandths, with increments of 5 thousandths. Their turn around is less than a week so if you aren't in a hurry you can just wait until you know for certain how much was taken off your head and/or block and then compensate accordingly to at least get it close to the factory specs. My block surface was quite pitted and needed ~6-7 thousandths taken off and the head had ~8 thousandths taken off so the Cometic HG I used was 70 or 72 (can't remember for certain) thous thick.
Hope this is useful.
EDIT: My contact at Cometic was Chris Workman. He was very helpful and should know what you are talking about when you are requesting a 1FZ-FE HG that might be over-bored and want different thicknesses, etc.
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- Thread starter
- #31
Very helpful! Thanks Mike and Beno!
I do have some patience, and i want to do this right. So i will wait for the machine work to be completed before ordering a HG.
I do have some patience, and i want to do this right. So i will wait for the machine work to be completed before ordering a HG.
A slight hijack if I may ?
You guys are discussing exactly what I need to know so I'm going to throw my 0.02 cents into the ring...
I'm doing a full rebuild and have ordered the Cometic HG since I'm going with the max overbore OEM pistons, the ones Beno references above.
My question to Cometic and Robbie: can I reuse my 'old' std OEM HG bolts that I pulled out ? I checked them per the FSM and they seem in spec. Does Cometic recemmend a different manufacturer/bolt ?
I also didn't know that the Cometic gasket was avail in different thicknesses ? They gave me a part number matching the piston bore and that's what I ordered. My head and block will be shaved 'ever so slightly': more to bring them in true spec than anything else.
Back to my original thought: if the bolts check out, why does everyone use ARP or something else ?
Thanks in advance to you all...jonathan
You guys are discussing exactly what I need to know so I'm going to throw my 0.02 cents into the ring...
I'm doing a full rebuild and have ordered the Cometic HG since I'm going with the max overbore OEM pistons, the ones Beno references above.
My question to Cometic and Robbie: can I reuse my 'old' std OEM HG bolts that I pulled out ? I checked them per the FSM and they seem in spec. Does Cometic recemmend a different manufacturer/bolt ?
I also didn't know that the Cometic gasket was avail in different thicknesses ? They gave me a part number matching the piston bore and that's what I ordered. My head and block will be shaved 'ever so slightly': more to bring them in true spec than anything else.
Back to my original thought: if the bolts check out, why does everyone use ARP or something else ?
Thanks in advance to you all...jonathan
- Thread starter
- #34
https://forum.ih8mud.com/80-series-tech/28710-winter-hi-po-engine-project.html
there is some discussion in this thread about them.
https://forum.ih8mud.com/80-series-tech/354381-my-turbo-build-finally.html
a little more discussion on them in this thread also.
On another note, landtank, how did you replace the oil pump bushing? I thought it was unavailable? That is one thing i am worried about. Even if i remove it before i send the block off, what if it needs replacing?
there is some discussion in this thread about them.
https://forum.ih8mud.com/80-series-tech/354381-my-turbo-build-finally.html
a little more discussion on them in this thread also.
On another note, landtank, how did you replace the oil pump bushing? I thought it was unavailable? That is one thing i am worried about. Even if i remove it before i send the block off, what if it needs replacing?
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I would not remove it, the chance of it going back in and having the same dimensions, concentric to how it was broken in are slim. I would just pressure wash the block then make the shop well aware of the bushing and it's unobtainium status.
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- #36
Bjowett made it look fairly simple in removing it "just in case". Never knew there was a "seating" or break in process on the bushing.
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Bjowett made it look fairly simple in removing it "just in case". Never knew there was a "seating" or break in process on the bushing.
All bearings break in to the surface that it runs on. Nether the bore or the bearing are concentric, even if carefully pushed out and pressed back in the exact same orientation it will be deformed and have to break in again, causing more wear. There is a very good chance that it is reusable. With any pressed in bearing, the best plan is to leave it in place, if it needs to be pressed out, it's best to replace it with a new one.
Personally I re-used my original head bolts when I did a preventative HG replacement on my old 80 @ 175K miles that was turbo'd and never had any issues, nor does the current owner to my knowledge. I think a lot of people more familiar with engine building than me like the torque-to-yield "stretchy" head bolts Toyota uses. But with boost, especially if you intend to go over 8 psi, I'd just not want to take any chances and do what most "tuner" folks do that are boosting Supra's to crazy levels - use ARP head studs. I think I might have just gone with the Supra set from ARP than worry about the hassle associated with the Opel set that requires trimming the front two. The Opel set has the shaft section that is "under-cut" so it is a smaller diameter than the threaded portion. The stock Toyota bolts are the opposite, the shaft is the thickest part and the threads machined down from that. Now does that matter? I don't know. I can say the ARP studs are very tough metal to cut through - I took ~3/8" off the front two with a diamond cut-off wheel dremel and that took much longer than I anticipated.
also, I edited my post above re: Cometic to include the contact info.
Great info.... Thank You !
I'll talk to Cometic on Tuesday and get their thoughts.
Rgds...
pressing the oil pump bushing in and out is pretty straight forward. My machinist made a new bushing out of navel brass as the factory unit had some wear.
