I just got my first 4 Runner. A 1995, with a 3.0. It has coolant in the oil. Previous owner said he thought it was a head gasket. I have also heard these engines are prone to have problems with the intake manifold gaskets leaking causing this problem. Will a compression check tell me which one it is? What should the compression be?

Changed the oil and drained the coolant. It will start and run. It is a little rough but not bad. has 112,000 miles on it.

mrfuzz

 

I wish I could help on the issue, Mr. Fuzz... Not a 3.0 guy... But I'd stop running asap if you're thinking/sure that you have coolant/water in the crank case....Last thing you want chilling out in the bearing journals or hanging out on the crank, right? I could be wrong on that, ....but I would think if it ends up being just a HG job(I know, "JUST"??? Sorry, but you know what I mean)....well, then you'd wanna flush the bottom end asap. I used ATF, .75 Quarts in the flush I did when I blew a HG on a brand new rebuild within minutes... Worked very well, suspended all the H20 and came out when draining....didn't have a TAD bit of steam when I started up with the new HG couple days later.

Sorry, don't mean to speculate, I'll be watching, wish ya the best, man!

 

the compression should be decently high and not fluctuate much between holes

here's the procedure http://personal.utulsa.edu/~nathan-b.../6compress.pdf

 

A cooling system pressure check would be more indicative of HG issue.

The only other way to get coolant in your oil would be if you have the optional (towing package) oil cooler on the driver side of the engine block directly back from the oil filter.

 

Put a compression tester starting from one side of the block on one cylinder, each cylinder should be at 150 give or take,
then if you reach one that has very low, or no compression put about 2-3 cap fulls of motor oil in cylinder.
If compression don't change it's a gasket or head if it does change it's the piston rings.

 

A leaking intake manifold gasket on these will only burn coolant. It will not contaminate oil as the lower plenum sits above the block rather than being a part of it. a faulty oil cooler or headgasket would be the culprit. More likely the head gasket if its running rough.

 

Compression test is not a reliable method to check for HG issues. When I blew mine, all six cylinders tested 205 psi within 2-4 psi of each other.

Also, the 3.0 stock psi is 172. 150 would be pretty low.

 

the timing chain guides can fail. then the chain will wear a hole in your timing cover. has it ever been replaced?

 

2.4 <> 3.0

 

roflmao~

 

^^ ha ha ha. i just did hg's on mine, if you have access to an overhead hoist leave the intake lower and crossover all bolted up and pull the whole top end as an assembly, its alot faster than disambleing all the way

 

Sadly, most of the 3.0 engines we get back for cores these days have cracked cylinder heads, along with the blown head gaskets. We see the majority of the cracks in the combustion chambers, but have seen plenty that are showing the cracks on the EXTERIOR of the head too (usually in the head bolt area starting just below the valve cover gasket surface.
If you decide to pull the heads, make sure to have them pressure tested and surfaced (properly!) before you re-install them. Save yourself the headache.

(edited, quoted wrong reply)

 

Have any of you guys tried the Steel Seal or Blue Devil head sealer? If so what kind of results did you have?

 

Using any kind of "block sealer", "head gasket sealer", or any of the other "quick fix" products out there are like putting a band-aid on a bullet wound.

Don't waste your time or hard earned money. Really.

 

Nope. Not believing it. Not for a second. Never heard of, nor seen, no such a thing.

Better yet...

Pics or it didn't happen!

 

Wow, really? I don't have a horse in this race, so I have no reason to make stuff up.

We have pretty much stopped building 3VZ's just for this reason. Lack of good core heads. Welding them is an option, but not one we were very comfortable with.

Sorry, I don't have pics, nor do we keep cracked heads around (convenient, huh?). It's been close to a year that we have built one, only for the reason they take too much time for the customer to wait while we source decent heads.

here are a couple YT threads by people that had cracked heads:

https://www.yotatech.com/forums/f116...w-went-113542/

https://www.yotatech.com/forums/f116...-input-205514/

I'm not trying to be combative to you and I'm not trying to steer the OP wrong. Just letting him know to have the heads pressure tested based on our experience.


Did you really have to ad this? Not cool.

You're probably just in the business of selling cylinder head pressure testing services. Then telling people they're cracked, so you can sell them another one and keep their core.






[QUOTE=MudHippy;51752771]
Nope. Not believing it. Not for a second. Never heard of, nor seen, no such a thing.

Better yet...

Pics or it didn't happen!

 

+1, this is correct.

 

I don't have to. But if I'm allowed to I will. Because I believe that what you are saying is highly unlikely to be true. I'm not saying it can't/doesn't happen. Just that it's merely a rumor until someone can show evidence of it being such a frequent occurance. And since there's no real evidence to suggest one should be overly concerned, there's no real reason to be overly concerned about the heads on a 3VZE cracking. If it ever happens, IT'S AN EXTREMELY RARE OCCURANCE. Like having a piston crack in one, as the #6 did in my 88. Did I make sure to document/photograph such a rare instance? See my threads...

 

Mudhippy knock it off. If you want a thread about who's had cracked 3.0 heads then go start one.