signalmtnyota

Hello all, I normally only read, daily, and never post, but I can't find the information I need.

I drove about 250 miles home this weekend in the fog and rain. Was doing my usually engine inspection and found that my dipstick was dry

So I checked the radiator to see about it and it literally looked like a chocolate milkshake. Radiator and reservoir had more oil in them than the engine. Now I've searched here on the forum for known causes and keep running across head-gasket and timing chain cover problems.

What none of these threads tell me is about engine power.

The engine doesn't tick at all right now. It cranks right up and runs well. (I didn't even notice a problem till I checked the fluids) Can it still be a head-gasket or a timing chain guide? Is there anything else that would cause this?

It did put white smoke out on startup, but it was cold outside and I didn't really smell a sweet smell in it.

84sr5yoty

It's most likely one or the other. Pulling the timing cover off is easier than the head. It would also be wise to replace the timing chain and components if they're still original. If you don't find any holes in the timing cover, pull the head next.

signalmtnyota

alright, thanks. guess i get to learn how to do a timing chain and/or headgasket now. I was really hoping there was something simple i had overlooked...

84sr5yoty

This site is a great reference for the timing chain job.

http://www.4crawler.com/4x4/CheapTri...ingChain.shtml

thook

You don't have to pull the timing chain cover. That's actually quite an involved procedure just to inspect. Pull the valve cover and look down into the assembly. If you've worn through the cover, the chain guides would have broken first.....which would be alot more apparent than being able to see a wear hole inside the cover. On the other hand, if you'd worn through the cover, that is something you would hear quite noticebly.

It's obvious you have a coolant/oil breach, but it's not making it into the combustion chamber. A blown headgasket would allow that, so maybe it's just the timing cover.

signalmtnyota

That was my thought exactly, and thats why I asked about this. I just couldn't understand at first how my radiator can be full of oil when I don't hear any noise or any loss of power...I guess I just get to tear it down till I find a worn part, starting with the valve cover.

thook

I'd mentioned the chain wearing into the timing cover making noise....???? It would sound like.....well....a chain rubbing against metal. You would definitely be able to hear it particularly with the hood up, engine running, and throttle opened to rev the engine.

signalmtnyota

I'll crank her up again and check that...and i'll get someone out there to help listen.

would it hurt the engine to crank it and rev it up like that if there's a bad headgasket or whatever's wrong?

I know I need to add oil before cranking considering its so low but what else can I do to help?

Also would a compression test do me any good at this point? I mean since it runs well I assume its ok. Or does a compression check do more than check for a bad headgasket and piston rings?

Forgive my ignorance, I've redone an entire hackjob SAS on this truck, redone the entire interior, but I've never done the engine work except for a water pump.

But I'm only 20 and a Mech Engr student who's not afraid to get his hands dirty.

thook

Well, you realize....I'm sure...the crankcase bearings are not being lubed properly at this point. So, yeah, there is risk to do more damage than has already been done. But, look at it this way. With what has happened and the fact it was driven as such you will need to tear the whole motor down to inspect, clean, and repair. It would be a good idea, anyway. So, running it for a few seconds is the least to be concerned about. Plus, you don't need to need to actually rev it high. Just run it and hit the throttle a bit. Hell, don't even rev it. Just start it and put a long screwdriver to the motor and the other end to your ear.

A compression test? You know the motor is running well (and it wouldn't if there was a loss of compression). You know the coolant and oil have mixed. So, it wouldn't tell you anything you don't already know. It would be of as much use in changing clothes when you know what you really need is a bath.

Since it hasn't seized up, maybe the damage is very minimal and all you may need is some new bearings and a good cleaning. But, you won't know anything until the motor is apart.

P.S. If you're really concerned and apprehensive, just pull the valve cover and see if you can spot any holes first. If the guide rails are broken, it will be easier to see. Likely it will be specific to the driver's side of the cover.

91Toyota

This won't work...there is a head in the way! You have to pull the head to see the guides.

corey 4 Runner

its probaly the head gasket it happen to my truck.

thook

Edited for greater kindness...

Actually you can. I found this picture today in another thread. You can't see the bolt right off for the distributor drive gear (my mistake), but you can see the rails.

thook

He already said the motor's running fine and he's not burning coolant. Unless, he's mistaken.

jasond

I bet its the headgasket also. If it was the timing chain cover the the engine oil would fill up with coolant, not the other way around. How would engine oil force itself into the pressurized coolant passages by running down the side of the timing cover?

jmcbmx

my truck was never really noticeable of the burning coolant but it was the head gasket. so i did it and the timing chain all at once while it was apart i had the intake plenum hot tanked and got all the carbon builup out of it and had the head completely redone and resurfaced and it ran real good. till it spun a bearing

thook

Well, you make a good point. But, once there's a hole in the cover, the system's no longer pressurized, either. And, how can a headgasket blow and not get coolant into the combustion chamber and still get oil in the coolant? Serious question. I don't see anything but coolant passages surrounding the cylinders at the deck surface. Are there oil galleries as well?

91Toyota

wtf are you talking about? Have you even taken off the head? Did you know that there is a bolt holding the head on right below/beside the cam gear? Yeah...you could probably see it...if you are a spider and can crawl down there. Please explain though!

thook

Yes, I have, and I know about the bolt....and it's not below/beside the cam gear, but in front of it (and would be visible were it not for a pool of oil). I'm in the middle of completely rebuilding my motor. But, the bolt has nothing to do with seeing the guides....nor does the head. There's an opening at the front of the head for the cam gear.....and I'm sure you know this.....and looking down in the opening you can see the guides to either side of the chain.

Edit: Actually, you're right. You can't see the bolt right off. See pic/post above.

aikinsmike

Have a question about my 85 SR5 22re. Backgound new engine 10k ago, now idles ruff about 750-800 normal on my truck is about 1000. stalls when I come to a stop but not ever time. new fuel pump, wires, cap, rotor, checked TB its clean. What gives?
Also replaced O2 sensor and one thread was stripped out do they thread in or do I need to weld a new one on?

thook

The problem could be neither the headgasket or the timing cover. Could be a cracked block. Has the truck ever overheated? Oil pressure loss?