first post but have been lurking on these forums for quite a while. anyways i have been working on my 91 pickup and it has the 3.0 v6.

well i got the valve covers off and for some reason everything under the passenger side cover seems darker than the drivers side. the passenger side also looks drier. In cylinder 1 i have 0 psi for compression so i have been working on tearing her apart to see what just went wrong.

here is what im talking about

shot from above


passenger side


drivers side

 

noe one?? not even a guess

 

Looks like that thing is pretty cooked. There should at the very least be small pools of oil in the head.

 

so what does that mean then.. is that head toast? bahhhh humbug

 

maybe the oil pump wasnt sending enough oil to the top of the head? how did it sound when it last ran?

 

good first post tho bro. glad someone searches and what not.

 

Yea, that looks strange to me. Since you have no compression in the #1 cylinder, you'll need to remove the head to figure out the problem, and you should get them both rebuilt. How was the oil pressure when it was running? You could have an obstructed oil passage or plugged filter that is cutting down on pressure in that area.

 

could be as simple as a plugged pcv valve. check the lines to the intake first. it's the cheapest thing first. since u have to pull the clean head off to check that, mine as well pull em both though just to be safe.

 

looks like it's darkest towards the back of the driver's side; isn't that the location of the problem cylinder on the 3.0's? the one that always runs hotter than the rest, and always has head gasket failures in that spot?

 

That's #6 on the other side of the engine.

Looks to me like you have no oil getting to that head for whatever reason. You are taking it apart anyways might as well get the heads redone too. Make sure the problem with poor head oiling on that passenger side head is not in the block if it is take it out and find the problem. Also remove the cam on that side and see hoe bad the cam journals are messed up I would be there FUBAR.

Jeremy

Edit: Looking closer looks like the other side is also quite dry just not as bad as the other, I would see if there is #1 oil in the pan and then start looking at the pump or filter. I would say that looking at it you may want to find a better engine to start with.

 

ah okay, see show's how much I know about the 3.0's but hell, I gave it a shot

 

it ran but not very good. it mad a really bad knocking noise on the pas senger side. i would put in a new engine but i cant find r for engines around here... there is no oil in the pan i drained it out a few days ago...

 

it looks like your cam caps are on backwards on the drivers side. also check your valve lash, your cam wear patterns dont look very pretty, looks like its running a little tight making the valves hang open.

 

Yeah I hate to say it but you got a lot of work ahead of you. Pull the engine and find out why there was no oil in the heads. I would say ether a bad oil pump or something plugged.

With no oil in the heads the cam wear patterns are going to be all over the place. There is a lot of bad going on in there. The cam caps are on the wrong way on the drivers side, not a good thing but will not cause the loss of oil.

Do you know if this engine was rebuilt at some point? I know the 3vz heads are very easy to get swapped (pass side on the drivers and vise versa) not sure what will happen when that happens but if I remember right the oil galleys will not be in the right spot. Do not quote me on that though, been a long time since I worked at Toyota. EDIT: I just remembered you can swap the heads from side to side but once you start assembly you can tell its wrong there a bracket that will not bolt on and the Dizzy.

I would take a look as soon as you take the head off make sure that the oil galley is lined up with the head.

 

im not sure it has been rebuilt but if the cam caps are on ebackwards it must have been,. the guy i bought it from was higher than a kite and i only paid 300 for it so if i need new heads or a whole new engine its not the end of the world. when i did a compression test cylinders 2, 4, and 6 were at 150 psi. and cylinder 1 was at 0 psi. and cylinders 3, and 5 were at 170 psi

 

if you were knocking, its time for a full rebuild with new oil pump. Pull the whole motor, its a lot easier to work on it that way. pull the pan and see what you find.

 

i think im going to do a full rebuild.. its kind of intimidating because i have never pulled an engine before. the most i have done to a car was a head gasket on an old plymouth reliant...

i am pretty mechanical though so im sure i can do it. Im going to go through and rebuild as much of the pickup as i can.. there is some rust on the cab which blows because i suck at body work

also what did you mean the cam caps on the drivers side are backwards.. i thought they are supposed to have the arrows face the cab..

 

Take your time and you'll do just fine. I used all EB parts and got the heads and crank machined. It took me about 3 weeks to do with only about 2 hours a night. I really took my time, chased all the oil passages, cleaned her really good. The truck now has over 300,000 kms on the rebuilt and it running strong.

As for the caps, I don't remember but I would have thought they need to face forward just like the marks on the pistons.

Good luck,

CT

 

do all your testing before you yank it, you will kick yourself when you have it all apart and everything looks fine. check cylinder leakage, compression wet and dry, and CHECK YOUR LASH. that really get some people every once in a while.

 

whats LASH