Outer Limits 4x4 Board

Posting this for a mate with a hj62 . Of late the oil pressure has been very high. Fitting a master gauge confirmed the fact dash gauge wasn't telling lies. Traced fault to worn pressure relief valve in timing case. Has anyone found if its possible to sleave the original timing cover to rectify this problem? Toyota don't have any new timing case’s in Australia ATM and retail price is aprox $1500 .
Any help with a work around much appreciated. I suggested him selling it and getting a GQ

I heard of a place that sells a custom plunger which is longer meaning it doesnt glide into the step whiuch is worn on the bore. I will try to remember who had this.

Many people have solved the problem by linished the bore slightly with a dowel and emry tape. I did this to mine just recently.

also replace the plunger when you linish the bore. Theyre about $15 with a spring from toyota.

The extended plunger would be a good fix. You could get one made up at an engineering show im sure. Shouldnt take long. Its pretty basic really. Just make the plunger about 5mm longer so that the step in the bore wont catch the plunger anymore.

See Picture.

picture

Thanks for that info, much appreciated. if you can remember who makes these modified plungers it would be a big help. Want this thing to be reliable. Nothing worse than having problems like this in the back of your mind during a trip.
Thanks again for the info so far.

I believe ENGINES AUSTRALIA in Dalby QLD do them.
I have also fixed this problem by drilling a hole in the case behind the valve so the pressure bleeds back into the sump. This was done with the engine pulled apart. Very hard to explain without pics -to hard now engine is running fine.

Thanks for the info. Would love to try the modified valve as it sure beats removing the cover. Worst coming to worst what size hole did you drill in the timing case to the rear of the valve?
Think I found the engine center you refered to
Dalby Engine Rebuilders
15 Loudoun Road
DALBY QLD 4405

1300555350

Tried calling but shut on weekends, will give them a bell on Monday.

It was the a size under 1/8 metric - 3mm if you intend doing this mod I suggest you get an old housing first to get the idea of where the hole has to go.

Got the new over length releife valve today, works a treat. Thanks for the info and heads up on its availability.

0xyg3n wrote:Got the new over length releife valve today, works a treat. Thanks for the info and heads up on its availability.

how much they charge you for it if you dont mind me asking?

$85 posted to melbourne. cheep considering $1300 for a new transfer case + gaskets+labour

0xyg3n wrote:$85 posted to melbourne. cheep considering $1300 for a new transfer case + gaskets+labour

wow, didnt think it would be that much lol

one from toyota is $15 with a spring lol

found out a few places make/stock them

engine australia has them for $48.31

Engine Australia

3/ 658 Beaudesert Rd Rocklea QLD 4106
ph: (07) 3875 1666

Will also be putting one in my 2H as I am still getting high oil pressure when the engines cold, even after I did an engine flush etc.

stupid question time...but what is considered too high for oil pressure?

cold and running temp?

G_loomis wrote:stupid question time...but what is considered too high for oil pressure?

cold and running temp?

toyota manual prescribes between 35 and 85psi at running temp (85 psi = 3000rpm)

cool....that means mine is running very sweetly

skootin wrote:I believe ENGINES AUSTRALIA in Dalby QLD do them.
I have also fixed this problem by drilling a hole in the case behind the valve so the pressure bleeds back into the sump. This was done with the engine pulled apart. Very hard to explain without pics -to hard now engine is running fine.

digging up an old thread

I notice you suggest drilling a hole to bleed the pressure back, i believe this is what the hole and recessed ring at the top of the piston is for? it lets the pressure bleed through the bypass hole when the piston is closed. (could just be for lubrication though)

with the worn piston there could be too much oil getting past which means the little hole cant keep up, which would explain why my pressure is fine (if a little low) when im at running temperature (thinner oil and plenty time for oil to bleed out)

Perhaps enlarging the hole in the side of the piston, or adding another hole(or two) could perform the same action as drilling a purpose bypass hole in the timing case.

I cant believe toyota would design this without thinking of the hydraulic complications of oil leaking past the piston, so im convinced the hole and "ring" in the piston is for this purpose.

I might also try getting another nut from the wreckers and drilling a hole in it to see just how much leaks past the piston, and this should also confirm it is indeed the pressure buildup behind the piston causing the problem, and not a step in the bore as many people seem to suggest (cannot feel a step in the bore myself).

You can get a longer plunger and new spring for about $20 bucks from to-jo 4x4 in toowoomba. This will fix the problem of the old plunger sticking