Question about timing belt skipping a tooth

[blazinjames]

Hey everyone this is my first post just picked up a 91 4runner auto with a 3.0L. I've been told the timming belt has skipped two teeth. I'm mechanically inclined but new to gas engines, timming issues and 3.0L.

It starts and runs but the engine doesn't sound right. It's really hard to explain. I want to look into this and make sure that's the problem wondering where I should start.

Do I need to pull off the timming cover and install a new belt make sure everything is timed and run it again or can I check some other way like with a timing gun?

I don't want to damage anything more then it already is and advice would be appreciated.

 

[blazinjames]

Anyone?

 

[541joseph]

Anyone?

The only way to find out is to pull fan shroud and everything off the front of the engine to get to the belt and check all the timing marks

 

[fo' runnin']

Here ya go bud... everything you need.

http://personal.utulsa.edu/~nathan-buchanan/93fsm/engine/67timingbe.pdf

 

[BlackWorksInc]

You should be okay in terms of severe engine damage, I believe the 3VZ-E (3.0L V6) is a Non-Interference if I remember correctly.

 

[blazinjames]

I pretty sure its not a timing issue..rev the engine up and I get lots of white smoke, did a compression test on the right side and middle cylinder was 100 front and rear were 150..need to do the other side tomorrow.

thanks for the link. that will come in handy.

 

[the_dingman]

While smoke is almost always coolant in the cylinders, and coolant in the cylinders is almost always a head gasket. The 3VZE is known for head gasket issues, so that's likely what it is.

Does the oil look ok, or does it look like a chocolate milkshake?

 

[blazinjames]

oil looks fine. I looked into it further today, on the right side cylinder from front to back were 120-90-and 0

so I have no compression in one cylinder, I have lots of blow by, when I pulled the pipe between the throttle body and air filter it was full of oil

 

[541joseph]

oil looks fine. I looked into it further today, on the right side cylinder from front to back were 120-90-and 0

so I have no compression in one cylinder, I have lots of blow by, when I pulled the pipe between the throttle body and air filter it was full of oil

That is what a head gasket does. You need to do a head job.

 

[blazinjames]

That is what a head gasket does. You need to do a head job.

well I guess I will do a head job.

does anyone know of a good write up or doing headgaskets on this forum or a site?

so besides all top end gaskets, timing belt water pump, thermostat, what else would you consider doing?

 

[541joseph]

well I guess I will do a head job.

does anyone know of a good write up or doing headgaskets on this forum or a site?

so besides all top end gaskets, timing belt water pump, thermostat, what else would you consider doing?

Cam seals for sure new coolant hoses. And whatever you see that needs to be fixed

 

[Ryros92runner]

so besides all top end gaskets, timing belt water pump, thermostat, what else would you consider doing?

Depending on how far you want to go in to it you will want to take a look at the upper pulley and tensioner pulley for the timing belt. The 1991 tensioner pulley will be sprung, not hydraulic.
You might want to replace the crankshaft seal through the oil pump.
After removing the plenum you will want to look at the PCV valve/hose/grommet in the passenger side valve cover.
You might want to service the injectors and associated seals in the intake. After removing the intake, the two other thing people write about most are replacing the knock sensor pigtail and inspecting coolant pipe #1 for leaks.
On top of the gaskets and seals you are likely to come across some toasted hoses and brittle wires so the costs add up pretty quick.
You will want the heads cleaned and decked at the very least, but more likely want complete valve job.Depends on what exactly is leaking. I know you've done a compression test but a leakdown test might help pinpoint the reason for the low compression numbers.
Just do your homework and figure out if it's worth the time and money to do this or look in to going with a rebuilt.
Head gaskets failing on the 3.0 are pretty common so there are many write ups on the 3VZE. Besides T4R there is YotaTech , Pirate4x4.Com - The largest off roading website in the world. and IH8MUD Forum.

Best of luck!

Jim S