Corvoid

Finally got everything reassembled after a long and laborious head gasket replacement. It's a 1984 22r 4x4. Back in June the head apparently failed and warped, which let massive amounts of coolant into the engine, so I decided to make this my late-summer hobby project.

I am totally not a mechanic, just followed everything I could read online and in the service manual, plus thanks to all yotatech supporters who have gotten me this far and responded to my earlier queries.

Not just the gasket was replaced: remanufactured head/cam/valves (which I got for $300) new timing chain, timing cover, new water pump, new oil pump and crank seal. The rocker arm assembly is the original...just reinstalled that. I also took the opportunity to remove all the antipollution hoses.

Much to my amazement (!) the truck actually started and ran for a while, after all my inept messing around. But there were some serious problems:

1. Very loud rattle sound, sounding something like valves.

2. Exhaust leak. I could see smoke coming out from around part of the exhaust manifold.

3. Overheat. After only about six minutes of the motor running. And the motor started dying, so I shut it off. The temperature gauge was up near the red.

4. Oil blackening. No coolant in it, though, thank god.

Now I feel like I'm in some serious trouble. I pulled off the exhaust manifold only to discover that I have stripped out some of the exhaust stud holes, which were all previously heli-coiled by whoever remanufactured the head. Some of the helicoils were destroyed by me and hanging out of the holes. I don't know why it overheated. I don't know what the loud rattle was coming from. The new timing chain and guides look alright from up top, but i have not pulled the timing cover off to look at the chain tensioner (which is new).

Not quite ready to give up (though sorely tempted!).

Any help, suggestions, or advice would be greatly appreciated. Not sure what to take apart next. I did check the valve clearances (they seem okay), and I ran a compression test, which also seems pretty good.

mwisham

The rattling is probably from the valves. There is a lot of discussion on this forum about valve adjustments. Being a professional mechanic for forty years, I prefer to set the valves a little on the loose side and just put up with the rattle.
You will have to re-install the heli-coils in the head.
Don't know where the over heating is coming from. It could be many things. Check the radiator to make sure it is not full of crud from the head gasket failure. Check fan clutch, thermostat, hoses, etc. You Must I repeat, MUST fix the overheating problem before going any further or you will blow another head gasket. Those aluminum heads can't take much heat without warping.
People have a lot of misperceptions about oil. If the oil gets black fairly soon after changing the oil, that means the oil is doing its job and is cleaning your engine Black oil is not necessarily a bad thing. If you think it needs changing, then change it. You would need to change the oil several times to get the crud out after the head gasket failure anyway. Personally, I run nothing but Mobil One synthetic in every engine I own. Cars, trucks, ATV's, lawnmowers, motorcycles, etc.
Don't give up there is a lot of good advice available here to help you out.

Corvoid

Gosh I really appreciate your support mwisham. My stamina and determination nearly went out the window when I heard the loud rattling and saw the temp gauge go up like that.

I'll be following all your advice, to be sure. I ordered a new exhaust manifold gasket (this time, a Remflex 7003), and also ordered a M10x1.25 helicoil set to fix up the stud holes i destroyed.

The cooling system failure is a huge problem. Not sure what happened there. The thermostat is new, but I guess it could have failed to open. Maybe I should double check the water pump, too? i happen to have a "heavy duty" fan clutch (still in the box) that I could swap on there as well, just to test it. No obvious coolant leaks that I could see.

The oil blackening was surprising...it was just some cheapo Valvoline 5w30 that I was going to use just for the initial warmup, to kinda clean the engine, and then discard. I had expected a lot of grit and crap from scraping and resurfacing the engine block, but not such a rapid fouling. Previously, before the head blew, I always ran full synthetic (Castrol 5w50).

Again, your support is appreciated tremendously.....thank you!

Corvoid

Just a follow-up.


First off, it seems likely i was running the truck way too lean. I had neglected to plug about six vacuum holes on the carburetor, which might (?) explain why it rapidly overheated.

I also took it upon myself the clean behind the valve cover baffle and replace the PCV valve. Behind the baffle (had to remove 8 bolts) it was absolutely clogged with tan colored oil froth and other dirt. As I was playing with that, I may have stumbled on the cause of the "valve noise".

As indicated by the red arrows on the photo, it looks like the rocker arms were colliding with a lip on the valve cover baffle. There are eight nicks or dents on the baffle lip, one for each rocker. The rockers themselves look undamaged, but each has a small worn spot on top where they were impacting the baffle.

Hopefully I did not overheat and kill my spanking new cylinder head with all of my naive incompetence.

nordicwargod

You wrote that the cam is new, did you compare to the old one? Measure the lobes with a dial caliper? This is strange?

Corvoid

Weeks later...and the cam measures to be about the same as the old one. Good thought, though.

What i did was take a grinding bit and remove the edges of the baffle in the eight places where the rockers had impacted it.

I realize now that those ding marks may have occurred years ago. There may have been a time when the valve cover had been overtightened.

Problem is, I still have the noise! i have posted a video link in another thread in this forum:

nordicwargod

That does sound to me like a valve cover impact. Can you feel it hit? Like I said, this is strange. I have heard studs impacting valve covers during installation and it keeps the gasket from sealing. Check out that rockerarm assembly?

Corvoid

I agree, nordicwargod. I was wrong in thinking the noise was coming from impact to the valve cover. Those ding marks on the baffle may have been there for a long time before i did this recent work. I used a mechanics stethoscope on the valve cover, plus felt it with my hand, and you're right, that isn't where the sounds seems to be coming from.

The rocker assembly looks okay. All rockers seem nicely centered on the cam lobes. I have checked the valve clearances several times, both cold and hot, and the adjusting screws are flat, so the measurements are pretty good.

Could it be the timing chain? The new tensioner that came in the kit seemed sticky compared to the old one. The old original tensioner seemed to operate very smoothly and took less finger-force to go in and out.

My latest guess is that the tensioner gets stuck in the "out" position after the oil pressure rises. When the truck warms up, and the oil pressure goes down to about 20 psi, it idles very quietly.

Give it some throttle, with a rise in pressure to above 30 psi (or when cold, as in the video, where the pressure is around 60 psi) the sound starts and gets worse.

Does it sound like chain slap?

nordicwargod

It did not sound like chain slap to me. Let others chime in about this as other opinions could be helpful. Easy to tell if its the tensioner, take off the cover and look if its pushing against the chain.
If it starts to make noise when the pressure is increased then I have no idea. Tapping noise soundded like it was from the valvetrain.
Just re-read from the beginning. You said lots of coolant got into the engine? Any chance you hydro-locked the engine and its a wrististpin?
This may be bad. Hope others have some more help

Corvoid

Thanks again nordicwargod.

i was lucky when he head gasket blew...only 2 blocks from my driveway, and when I got the head off, there was only about 3-5 mm of coolant sitting on top of cylinder 3.

If there were hydrolock damage, particularly to a wristpin, wouldn't the spark plug wire removal test show something?

I'd rather not remove the timing cover again if I don't have to, just to check the tensioner, on what could turn out to be a wild goose chase.

It would be great to get some more opinions on this before I undo my nicely gasketed and unleaking new timing cover and waste another 5 hours on this.

nordicwargod

I'm sorry, I meant valve cover. Stick a good light down there and you can see the tensioner. You can also tell by feeling that side of the chain. If the chain flops around on the passenger side you have a problem with the tensioner and in fact that noise would have to be timing chain related.

Corvoid

My bad, I misunderstood.

From what I can see up top, the chain looks to have decent tension on both right and left sides. It's not easy to see the tensioner, but I think the tensioner arm is extended (maybe it's okay?). And from what I've read from others having tensioner problems, it's usually a failure to keep tension on the chain, not failure to relieve the tension, which is what I was guessing.

When using a stethoscope on the motor, it's really loud when putting it on the valve cover acorn nuts. Especially the two on the intake side.

My latest guess is that the noise is something in the rockers. Maybe it's just the valve clearances.

Back around 1987, I remember taking the truck to a Toyota dealer when I had "valve noise". They installed those two-piece rocker arm spacers. I wonder if those are still okay....

nordicwargod

What is a rocker arm spacer? Where does it go?
Well, there is one way to find out quickly. Loosen the acorn nuts to finger tight and start the engine. Hold down on the cover and then take them off. Lift up the cover and see if the noise stops. May be a little messy but you will have the answer to this question.
Clean up as much with a towel/rags and toss them. Buy some simple green and spray it on straight where the oil came out and hose down. Put a cheap harbor freight tarp down first.
Let us know??????

Corvoid

Hey thanks nordicwargod.

Regarding removing the valve cover: I like your idea, and I'm just about ready to do like you've suggested.

The farthest I've gotten is loosening the acorn nuts to relieve any pressure on the cover. By then, it was already raining tiny oil droplets all over. It didn't make any difference in the noise.

The old rocker spacers are still on my rocker assembly. There are three of them, all near the rear part of the valve train. A great picture of the spacers can be seen here:

http://www.celica-gts.com/forums/ind...topic=13356.15

nordicwargod

OK, I see what one of them is. Why are they used on your engine? Don't the rocker arms line up with the cam/valve stems If not then why. Do you have a hybrid set up? What block/ head combination do you have where you need those?

nordicwargod

I think if you raise the rear of the truck until the engine is level a lot of the oil draining over the rear and down onto the bell housing would instead drain into the valleys in front and back. Use a carpenter's level on the valve cover and jack it up.

Corvoid

Thanks nordicwargod.

I'm scared schmidtless about running the engine with no valve cover on.

After some additional reading, the next thing I'm going to try is re-adjusting the valves. But in a different way.

Some posts have mentioned doing the valves one by one, instead of as groups of four. This involves looking at the cam lobes individually, trying to see them reach their lowest points as you turn the crank, then doing the adjustment for that one valve.

Since I'm dealing with a remanufactured cam, I guess it's possible the lobes might be a little off from each other?

Also, I'm going to try a test when I put some goop in the oil, like Marvel, to see if that changes the rattle noise.

nordicwargod

Scared shmidtless huh? Won't hurt anything, but may be a little messy. All you have to do is lift it up and if the noise stops you have an answer.
If the noise continues you valve cover is already be loose and then you can adjust your valves.
Marvel mystery oil won't do anything for the noise. Something is hitting. I think its something hitting the valve cover.

Corvoid

Alright, i guess i'll try it. Might as well be scientific and do everything. The valve cover was always the prime suspect.

Thanks for hanging with me on this....it may be a couple weeks before I can work on the truck, due lack of available daylight and time....but I'll report back as soon as I do anything.

dark_fairytales

if its the valves, those are the loudest valves I have ever heard. I hope it is not something deeper in the engine, like a rod or wristpin.