3sgte head gasket Options

[rjbibeau]

hey sup guys i'm helping my girl with her sw20 3sgte project. we just pulled the head off the engine yesterday because it blew a gasket and well it did and it was in the 3rd cylinder. first question is...there is a streak of corrossion from the coolant that leaked into the cylinder on the walls and i tried getting it out with some wd40 and it's barely coming off. it's a raised corossion. will it hurt the rings if i can't get it all off or will it be allright. next question is we put the crankshaft at tdc and when we took the timing belt off the right cam as you look at the timing side tweaked back a bit but the left was just fine so i'm like crap so i look at the mark on the cams and the left cam is deece but the right one is a lil off from the marks. when i try to turn the cam to correct it..it seats back to where it was beacuse the valve springs are forcing it.

when the engine was in the car it had a wierd shutter sound kind of like metal on metal when it was under load from like 25-3500 rpm but then went away as the rpms increased, i figured it was a idler pulley problem but i checked em and the looked fine. there wasn't any slop at all in any of the pulleys. could that one or two degrees of being off in the timing belt cause that type of sound. there were two yellow marks on the cam pulleys and thought maybe someone else was there doing a belt job.

now for the timing tensioner that is such a wierd tensioner i understand i need to compress it with a vise and shove a pin in there and install it and mount it up and pull the pin back out like a grenade for it to retain tension. could the timing tensioner be going limp when it's under load and the #1 idler puller be slapping itself on it's mount.

any input would be appreciated.
-Rick

[x_itchy_b_x]

Do your streaks look like that? if so then yes they will affect the rings and compression.
you will have alot of blow by.


To make sure your at TDC use a dowel or screw driver and place it in cylinder number one.
crank the motor until the piston pushes the screwdriver to its maximum height. you can be more precise by using a feeling guage. I wouldnt go by the marks on the crank, as mine was about 4 degrees off from actaul Zero.

For the cams, are you using the marks Under the valave cover? those are the correct marks to go by.
some people make the mistake of using the creases on the black metal plate that is right behind the gears.

The sound could have been incorrect timing and cause detonation which blew the head gasket, and possibly did more damage.The tensioners dont usualy go bad, if its hard to compress in the vice than its fine.
for the pin use a small alan wrench becaus they are pretty strong for there size.

Hope that helps.

[rjbibeau]

the streaks look similar but you can scratch it somewhat with a fingernail and it's just built up coolant. would a wire brush be alright to take to the cylinder wall. i'll post pics up in a lil bit. so how did you fix the streaks on your engine?

[x_itchy_b_x]

its on a truck to new mexico right now to get bored out and honed with forged, blueprinted, balanced internals.

if you can feel the streak will your finger nail its bad. if you can tell its rougher than the rest of the cylinder wall the rings are probably worn also, not just the cylinder wall. so its hard to say what you should do. who knows how long it will last before it starts to leak compression.

[rjbibeau]

when we took off the timing belt the exhaust cam jumped a bit and it want to be seated in the position when you try to move it to make the holes on the cam line up it jumps back. here are some pics of what i'm talking about i don't know if these are the right markings or not. if not what is another way to make sure the head is at tdc?


exhaust



Intake



Both intake and exhuast


when we put the motor at tdc and took off the timing belt the exhust cam jumped a lil bit and it seems to be seated in that position meaning it's a lil hard to move it. when we took the head off we noticed the first cylinder's vavles were fully closed but on the 4th cylinder two of the valves were just a tad open but diefinately not fully seated is this supposed to be like that? could the valves need adjustment?

This post has been edited by rjbibeau: Jun 22, 2007 - 2:35 PM

[x_itchy_b_x]

just grab the exhaust cam with a wrench and pull it back a hair so it lines up with that mark. the fact that it wants to jump is fine. when you put the timing belt on it should hold it from jumping unless the belt is stretched.

[rjbibeau]

k thanks i'll give that a whirl tonight how about the 4th cylinder's valves

[toyotacrazy]

k thanks i'll give that a whirl tonight how about the 4th cylinder's valves

What HG are you using?

[Insanity-74]

If I were you I would replace the cam belt tensioner...better safe than sorry...I have seen a few 3sgte engines give up when people havnt replaced the tensioner....I`m not saying that that was the cause of the failure, but its likely........and for all the people that are bound to say..."well its not worth it just leave the old one on they never go wrong"...for the sake of a few $$$ I`d do it for peace of mind.......like I say better safe than sorry

[scothaniel]

Dont laugh, but if you want to remove the rust with little or no work, pour some Coke in there and let it site over night. I've done this on an ST205 motor I had imported and it really works.

The cams usually sit just off the marks when there's no tension. Once the tensioner is on, it should line up perfectly.

[rjbibeau]

k thanks i'll give that a whirl tonight how about the 4th cylinder's valves

What HG are you using?

felpro

[alltracman78]

Meh

IMO use OEM or a good [HKS, TRD, Cometic, ect] MHG.

[rjbibeau]

cometic are touchy you have to get the block and head milled

[x_itchy_b_x]

cometic are touchy you have to get the block and head milled

Most Multi layer steel gaskets need the block and head milled.
depending how straight and level everthing is sometimes you wont need it machined.
any updates on this?

[rjbibeau]

we're dropping it in soon...the tensioner just came in and now we just have to find the time to drop er back in i'll keep everyone posted