oil starved to the head?

How-to's and repair secrets for your 4WD can be found here. Have a question? Ask it in here!
Post Reply
User avatar
Petros
Highest Ranking Member
Posts: 11185
Joined: Sun Jan 28, 2007 6:31 pm
My tercel:: '84 Tercel4wd w/extensive mods
Location: Arlington WA USA

oil starved to the head?

Post by Petros » Mon Jun 27, 2011 9:06 pm

On this project '84 Tercel I have been working on I made another unwelcome discovery. I bought it at a fairly cheap price because the seller said it broke a timing belt, when that happen the belt wrapped around the tensioner and managed to break off the front of the oil pump. Odd, I have never seen that before. supposedly all it needed was an oil pump.

So I manged to drop the pan, remove the damaged oil pump, install an new pump, tensioner and timing belt, along with a new main seal. when I had the pump off I noticed the oil pan appear to have a lot of slug in it, this engine was an imported 3ac that the previous owner installed. IT was kind of odd too, some of the details were strange, the timing belt cover for example has the bolts holes in different locations, and the "toyota" on the valve cover is the other way around, opposite from all the others I have seen. I do not know why toyota found it necessary to change these details, but they did for what ever this engine came out of.

Anyhow, I put oil in it, installed new battery and proceeded to get it started Saturday. It was really struggling to run, but I got it to rev up to about 4000 rpm, but very weakly. than it stalled, and would not start. The timing belt I installed had broke, defective maybe, was damaged sitting around too long? Next day I pulled the front cover off to put in another belt, and when I tried to reposition the cam to TDC, it was impossible to turn, the cam was seized. So I pulled the valve cover, and removed the rocker shaft assembly, cam still would not turn. I notices the rocker assembly looked dry, not all covered in freash oil like it should have been. I pulled the cam bearing caps and found the front bearing race was scored and frozen. Looks like no oil. I squirted carb cleaner into the oil passages and all were clear, at least in the head.

It made me wonder if the whole engine was getting no oil, and if this was the reason the orignal timing belt broke that damaged the oil pump. Now I am wonder what kind of shape the connecting rod bearings are in.

So my question is what could possibly make the head, or the whole engine, starved from oil?

Could sludge completely block off the oil pickup screen? If so, can I pour some kind of strong solvent down into the oil pan to dissolve it, and drain it out. What would you suggest?

I am going to check the oil filter to see if it got any oil when it briefly ran, if so than it is a problem to the head only. I am also going to crank the engine with the cam out to see if I can get oil pressure up in the head. What could make the head oil starved?

At worst I am going to have to do what Bluebelle's mom did, drop the pan, clean it out and check/replace the rod bearings. AT best I can clear the problem without so much work.

This was supposed to be an easy fix. I have found most times I have bought a "fixer" there were always much bigger problems than what the seller thought. Oh well, I buy a non-running car and I take my chances.
'87 Tercel 4wd SR5 (current engine swap project)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)

4wdchico
Highest Ranking Member
Posts: 563
Joined: Sun Mar 30, 2008 6:51 pm
My tercel:: 1985 tercel 4wd
Location: Chico, Norcal

Re: oil starved to the head?

Post by 4wdchico » Mon Jun 27, 2011 9:21 pm

If there is no oil in the oil filter you will have some hard choices to make for sure. Do you still have tho old oil pump? If so you could look inside it for signs of being run dry. Only once have I ever seen an engine so sludged up that the pickup screen was blocked. The stuff was like tar but smelled even worse, if you can imagine that.

danzo
Highest Ranking Member
Posts: 537
Joined: Fri Dec 05, 2008 11:01 am
My tercel:: '86 SR5 6 speed
Location: The Colony, TX

Re: oil starved to the head?

Post by danzo » Tue Jun 28, 2011 7:25 am

Sorry to hear you're having bad luck with that car Petros. I would think if the oil pump strainer was sludged up badly you would have noticed. Have you hooked up a mechanical oiI pressure gauge to see if there's a blockage? I found a neat product that allows you to do this and leave your oil light senor intact, and you can also install two other lines: http://www.glowshiftdirect.com/oilfilte ... nf-16.aspx When I installed it on my Terc I discovered the oil pressure is a bit too high with 20-50, so I'll switch to 10-30. Hopefully unleash some hp 'n' mpgs.

Sometimes you luck out with a non-runnner, other times it's a bit more involved. Good luck and let us know what you find.
It's a scientific fact that in a twin engine aircraft, when one engine fails there is always enough power in the remaining engine to make it all the way to the crash site.

User avatar
Petros
Highest Ranking Member
Posts: 11185
Joined: Sun Jan 28, 2007 6:31 pm
My tercel:: '84 Tercel4wd w/extensive mods
Location: Arlington WA USA

Re: oil starved to the head?

Post by Petros » Tue Jun 28, 2011 12:30 pm

i have the old pump, I tried removing the cover but several of the screws are really stuck, they would just get buggered up with an impact screw driver on it. Got all but two screws off, was considering drilling out the stuck screws but set it aside since I had no reason to get the cover off other than curiosity, now I have a reason to inspect the pump however.

I did not get a chance to inspect the engine last night, hope to get to it tonight. So could have oil starved to whole engine, or just to head. If it just to head the only thing I can think of that would cause that is blockage in the head oil galley. I can pull the front plug off and run a brush through it with lots of solvent and blow it out.

If it oil starved to the whole engine it could be a bad oil pump, oil pressure relief valve (they can get stuck open), or blockage in the pick-up, or oil galleys in the block.
'87 Tercel 4wd SR5 (current engine swap project)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)

shogun
Highest Ranking Member
Posts: 784
Joined: Thu Mar 31, 2005 1:48 pm

Re: oil starved to the head?

Post by shogun » Tue Jun 28, 2011 2:48 pm

there are sime 3ac engines that are used in tokio taxis that are a bit different since they are mounted transversaly, maybe they used a low quality head gasket and the oil passages are too small, i had an engine over heat for that
tercel 4wd custom suspension, under drive pulley, vented brakes, cold air intake, and plenty more to come

Jarf
Top Notch Member
Posts: 343
Joined: Sat Jun 21, 2008 9:20 pm
My tercel:: Currently without
Location: Borden, Ontario

Re: oil starved to the head?

Post by Jarf » Wed Jun 29, 2011 8:39 am

Back in the day, we used to do a lot of JDM engines, most were fine but sometimes we would get odd configurations.
The biggest difference was usually oil pan and sump location.
I would take a close look at what you have, if they had to swap the Terc stuff into it, they may have forgotten the o-ring on the pick-up tube, easy mistake, horrible results.
Might be worth checking out.

User avatar
Petros
Highest Ranking Member
Posts: 11185
Joined: Sun Jan 28, 2007 6:31 pm
My tercel:: '84 Tercel4wd w/extensive mods
Location: Arlington WA USA

Re: oil starved to the head?

Post by Petros » Wed Jun 29, 2011 11:07 am

I found the problem, it was the pressure releif valve was wide open. Removed the pan and pick-up, it was clear (the pick-up tube uses a small gasket, not an o-ring btw). I cleaned out the relief valve with solvent and made sure it moved freely. The oil pump had come from a running engine, but had been sitting around in parts boxes of mine for about 7 or 8 years, I should have checked it more closely.

Also pulled ed the rod bearing caps, and it looks like the engine will get a connecting rod bearings as well. Oh well, stupid me. Should get it all together tonight, will now have new oil pump, timing belt, cam and main seals, oil pan gasket AND rod bearings.
'87 Tercel 4wd SR5 (current engine swap project)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)

Post Reply