Alright guys bought a supra and thought the engine was good but I tore it down and the first thing I saw was scouring on the journals of the cams and the caps, I did research about this and it apparently is "normal" im just not buying it, also the car had a blown head gasket and im gunna get the head resurfaced but not the block, im using the cometic head gasket, do I need to resurface the block as well or can I just leave it like that?
7mgte cams
- Thread starter Miguel
- Start date
You need to resurface the block for a mhg to seal properly.
The scouring is common but not normal. Personally I would look for a better head as that could cause problems down the road.
The scouring is common but not normal. Personally I would look for a better head as that could cause problems down the road.
The Journal scouring is pretty common unfortunately. If your lucky the cams take all the abuse and the heads are still it good shape. If not lapping the caps down a bit and having it line honed is your only option.
As for the block, YES it must be resurfaced if you want to run a mhg. Lapping afterward is also a good idea, you need a finish of 50 RA or better (30 + ideally).
As for the block, YES it must be resurfaced if you want to run a mhg. Lapping afterward is also a good idea, you need a finish of 50 RA or better (30 + ideally).
Alright I have arp head studs and a genuine oem headgasket from toyota, the car used to push 16 psi, is that a correct setup to go? Or a metal head gasket
If your going 16 psi (or higher) strongly recommend you go with a metal head gasket. It is extremely critical that the block and head are prepped properly or don't waste your money and stay with the OEM headgasket.
my opinion.
my opinion.
Got it. Also the car used to have a metal head gasket and ive searched around here and the web and apparently you can reuse the headgasket?
You can, but I function on cost vs effort. To use a new one is minimal cost compared to doing it twice.
My cams were scored. Some fine grit sand paper cleaned up the journals nicely. Machine shop cleaned up the head and caps at no cost with my head machining.
^ Did you check the clearances between the cam & head journals after all of this or have the shop do it?
Hmm nice info I might do that too, did I check the clearances? Im waiting for my check to buy a micrometer, apparently I have to remove the whole engine and tear down everything just to resurface the head, some say to sand it and clean it good and im ready?
Typically the scoring is in a soft babbit material on the cam journals and bearings. Has a strong sulfur smell, and can be marked with your fingernail. If that is what you see, it is not an issue.
GC89;2047619 said:
No, because im a poor redneck. No but seriously. Mine was scored from what looked like lack of oil, but in the 10,000 miles i owned the car prior, i had not run it low. So it had been running with the scoring for a while. The machinist said he didn't believe it would be enough to make a difference, but I know the tolerances were opened up from cleaning up the scoring, but new cams are freaking expensive. Also good used heads are unicorns. If it didn't work i was going to have to get a new head most likely, and/ or new cams. If that happened i was going to get some bc stage two cams. So far 5,000 miles later its working fine, but its still in the back of my mind.