Head Gasket on a 20R engine????? (2 Viewers)

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Hey everyone,
I think that the head gasket on my 79 4x4 short bed p/u is blown. The truck only has 37,000 miles on it and it sat for long periods of time since 79. Well here is the problem it is blowing HUGE amounts of white oderless smoke. It seems that it does it when you are decelerating and when you rev it at idle. When you are moving down the highway the smoke clears up. It did this once before for a short while then it went away. Now it is VERY bad. The smoke was starting to go away, the I checked the rad and it was low, so I added antifreeze and the smoke came back in full force. So does it sound as if the head gasket is blown?

How hard is it to change the head gasket? How much should I expect to pay a shop to do the work? How long should it take to do the job? Is there anything else I should look at when doing this job?

Thank you,
Zack
 
Sounds like a HG to me, you can do a compression check if you'r not sure.

Not a really hard job if you have a good manual for it. If you had all the parts, it can probably be done in a day. But you may need to have the head milled if it's warped (probably not)

A new timing set wouldn't be a bad thought, maybe a water pump too, and a new main seal. It's all that extra stuff that adds time on to the job. No idea what a shop would charge, I only pay them to smog me. :)
 
A compression test will only tell you that you have low compression, but it won't tell you where it's going. Try to do a leak-down test, but I also think you've got a leaking HG, especially since you say it's using coolant.

That engine has a double-row timing chain with metal guides from the factory. I wouldn't bother changing them, they should last longer than the rest of the truck. But I would definitely put a front main seal in, it's really easy.

Maybe have the carb rebuilt? It's probably all varnished up from sitting with old gas in it for so long.
 
True a leak down test is better. If you can't or don't want do get into the leakdown test equipment, you can just set each cylinder at TDC and put some compressed air into the spark plug hole. Then listen at the intake, exhaust, and the radiator cap to see where the air's escaping if anywhere. Much cheaper that buying or making a leakdown tester.

Is there coolant in the oil? Or oil in the coolant?
 
Well if you got enough water in the c-chamber to blow white smoke, you'd have 2 problems:

The truck would run like s*** and
When you went to crank it again it would "hydrolock" and you'd be done

$1,000 on a hole in the water jacket around the exhaust ports. I had a 20R do the same thing, pretty common.
 
Bear80 said:
Well if you got enough water in the c-chamber to blow white smoke, you'd have 2 problems:

The truck would run like s*** and
When you went to crank it again it would "hydrolock" and you'd be done

$1,000 on a hole in the water jacket around the exhaust ports. I had a 20R do the same thing, pretty common.


So caN THe above be fixed? Hole in the water jacket? How does that happen? When it first blew the white smoke then I shut it off, then attempted to restart it. It seemed like it might have been "hydrolocked" but then after a few cranks, it started again. What can I be facing in this repair, is my engine toast? It still starts and runs. So any ideas??

Zack
 
Also I got the new parts from Toyota. I got a new water pump, and a head gasket kit. It seems that the "gasket kit" has a lot of different gaskets to it. Does anyone know the kit that I am speaking about? Is there anything else that I should get before the job starts? I also got a new thermostat and rad hoses.,


Zack
 
well if that is the problem a shop may be able to wled it up, but you'd be better off getting anothing head. It seems the heated water around the exhaust ports just eat into the metal. when you say it seemed "hydolocked" do you mean it didn't crank right up? had trouble turnning over? what? hydrolocked means..locked. Belive me you'd know it. I had a small head gasket leak, enough to blow some smoke and run like s***. After setting for 10mins. the small amount of water that got in was enough to hydrolock the engine.

I would like to know how the engine was running when the smoke started. That will be a huge clue to the problem. You can leave the intake and exhaust manifolds on the head but it takes 2 people to lift it off and put it back on. But if the problem is like I said, you should pull the exhaust manifold before you pull the head and check for any leaks. Just make sure you follow the book about keeping the timming chain from sliping off the crank. I think alot in that head gasket kit is dependant on what you take off. Usally they come with an intake, egr and plumbing, and exhaust gaskets. The worst part of the job is scraping the old gaskets off and make sure not to nick the soft metal of the head. I could probably get the head off and back together in 4 hours easy, sorry you aren't closer. good luck!
 
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Take lots of pics of how all the emission stuff is hooked up before, and while you're taking it all apart. I just finished a total rebuild on my dads 22R and I took just shy of 100 pics durring the whole thing. I only ended up needing a few of them to confirm where stuff went, but you never know which one it'll be. Not a real bad job. Remove the hood right off, it'll get you better light and no hood prop in the way. Let us know if you need any info.

Get a tube of this:

http://www.shop.com/op/~Permatex_The_Right_Stuff_Gasket_Maker_Caulking_Gun-prod-17006459

use it instead of the pre cut gaskets on all the coolant/oil sealing areas IE water pump, timing cover (you may want to think about a timing kit while you're in there) thermostate housing also.... Best of luck.
 
2ndGenToyotaFan said:
Get a tube of this:

http://www.shop.com/op/~Permatex_The_Right_Stuff_Gasket_Maker_Caulking_Gun-prod-17006459

use it instead of the pre cut gaskets on all the coolant/oil sealing areas IE water pump, timing cover (you may want to think about a timing kit while you're in there) thermostate housing also.... Best of luck.


I strongly advise you to use the toyota gaskets. Do not use any other type of gasket than what Toyota calls for. period. In your case, a 20r should not need a new timing kit. The 22r's use plastic guides vs. the metal guides used on the 20r's. Also there isn't any reason to pull the waterpump or timing chain cover. If you pull the timming chain cover you will need to pull the oil pan and re-seal it. Keep this a day job and not a full weekend project. :cheers:

I just rememberd that the timing chain tensioner does take some wear. But as I recall mine with 250k was still ok, not such a big deal but probably worth changing if you are in the front cover. Like I said though keep this a day job. BUT you can pull the front cover off without pulling the head, even though the book tells you to, though you'll still need to pull the oil pan. I had to do this on my truck to replace the gasket because it started leaking.
 
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I deff want to keep this a one day project!! I did buy a new water pump, I hope that does not make things that much harder/longer. However what is making me nervous is the "water jacket" hole. I hope my truck is ok.


Zack
 
Would it still run if a water jacket was bad? It runs now and when you top off the rad, the smoke seems to increase.

Zack
 
Toyota has their own FIPG (form in place gasket) stuff that they recomend on lots of stuff. Bottom line is goo seals better than pre formed gaskets. I used the right stuff on my oil pan and had to pound a screw driver in between to get it off again. Doing so scrapped the sealing serfaces pretty bad. But I used the right stuff to put it back on and it's not leaking a drop.

Take a read here. The guys got a little side tracked, but lots of good opinions on goo.

http://bbs.off-road.com/ubbthreads/...ds=+87XCToyota&topic=&Search=true#Post1185907
 
Zack1978 said:
Would it still run if a water jacket was bad? It runs now and when you top off the rad, the smoke seems to increase.

Zack

yep I'd say the head has a hole some where in the exhaust ports. If you can still crank it and it runs, then water most likely isn't getting into the pistons.

pull the exhaust manifold and take a look. then check around at some shops about welding it up. The only problem would be that there is probably other areas that are about to "pop" a leak. a new head would be the best solution if your old head does have a hole,crack, etc.
 
2ndGenToyotaFan said:
Take a read here. The guys got a little side tracked, but lots of good opinions on goo.

http://bbs.off-road.com/ubbthreads/...ds=+87XCToyota&topic=&Search=true#Post1185907

well I can't give credit to those guys that did not RTV the oil pan. Toyota never calls for anything else. I agree there are aplications that require RTV etc. I still would never use it in place of a gasket, when one is called for. The only issue I had is that my front cover gasket started leaking a few thousand miles after I rebuilt the engine. I did apply "form-a-gasket" on the new gasket when I replaced it. However this stuff does not dry into a seal like RTV. For more reasons than I have time to write, I'll just say that awhole lot smarter guys at toyota figured out what type of gaskets to use in each application.
 
Bear80 said:
yep I'd say the head has a hole some where in the exhaust ports. If you can still crank it and it runs, then water most likely isn't getting into the pistons.

pull the exhaust manifold and take a look. then check around at some shops about welding it up. The only problem would be that there is probably other areas that are about to "pop" a leak. a new head would be the best solution if your old head does have a hole,crack, etc.



Well in fact it does run, and I also checked the oil, and it does not seem to be contaminated with water/anti-freeze. If the head is bad, where can I find a new head, and what price am I looking at? And why would the exhaust port blow a leak?



Zack
 
well a junk yard would be my frist place to look. and then price is dependant on each yard. there should be shops around that sell "re-manufacted" heads etc. usally these are engine shops that sell short/long blocks. I want to say my 22re head with cam was right around $100.

As far as the port blowing a leak, I think it's just a 20R problem and over the years the water eats away at the metal.
It'll all make sense when you get your head off and see the problem.
 
I'm with Bear80. Get the OEM gasket kit for your engine, only use RTV/FIPG where Toyota says to in the FSM. Smearing RTV all over the place is a true sign of a novice mechanic. It's a total PITA to clean up these messes.

True, Toyota does sell a very good black FIPG, but they don't use it very often. The '85+ 22R/RE engine uses FIPG for the oil pan only, the older 20R/22R uses a cork gasket, but you put a dab of FIPG at the interface of the timing cover at the pan just to seal that joint. That's all I've ever used, and they never leaked.

Get a die grinder and some extra-fine Scotch-Brite pads, use them to clean up all the gasket faces. Install the paper gaskets, torque as spec'd. Works great.
 
Well the plow truck is at the shop right now, and I hope all is ok with the head. I will kepp you updated when I get the truck back.


Zack
 
Have the head checked for warp.
If you don't and it is warped, you will be repeating this HG replacement, if you want more insurance have it magnafluxed for cracks.

Trust me on this warp thing, my nissian hard body and my 22r both did me in.
can't stress checking coolant level enough now, I do it almost twice a week.
 

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