Oil pump or cover gasket?

Have a nice oil leak at the front of the engine. Took my 1st gen 2.7 to a mechanic. Said oil leak is from the oil pump and head need to come off. Big job his shop is not wanting to do. See lots of posts about the oil pump cover gasket. He says he’s pretty sure it’s the pump and would require tearing into the engine. I don’t see significant pools under truck but the skid plates seem to be a collecting oil. Is it worth paying someone to do this job? Or just watch and wait. These trucks are worth saving, just not sure how worth it.

 

So I’m bartering with a master tech where I work. If he does pull head and replace oil pump, anything else I should have him do while in there? Timing chain? Or leave it alone? Probably have him knock out water pump and belts while doing the job. Truck has 192k miles and want it to go to 300k plus so I see the value. Any input would be great!

 

Why does the head have to come off to do an oil pump? I did mine on my 2.7 in 30 minutes when the oil pump cover was leaking. Skid plate, belts and harmonic balancer is all that comes off to replace the oil pump on the 3rz.

 

I think the mechanic just didn’t want to mess with it. So he insisted the job was too big and didn’t want to do it. I’ve seen numerous posts not mentioning head removal, but also see people quoting a service manual saying “step one: remove head assembly”. How tough is it get off the main pulley?

 

Only reason the head would need touched is if it was the timing cover itself leaking, not the oil pump. The oil pump covers are pretty common for leaking on these engines though and that is a simple fix.

Once you get the bolt broken loose the pulley slides right out. The bolt is pretty tight though. I just put a breaker bar on it and put it against the frame and bump the key. Probably the most problematic part of doing the oil pump cover is that they have Phillips head screws from the factory which can sometimes be a pain to remove. Lc engineering sells a complete kit for fairly cheap that comes with a new pump, cover, seal and upgraded cover bolts.

 

Thanks! The mechanic insisted head had to come off bc “leak is from oil pump”. I kept saying I’ve read all the posts on here and he said I have 20 years experience, I’m right, but I don’t want the job. Good to hear that an amateur can handle it. Still may have the service manager do it at my store. What’s a fair offer for him to do it if I buy all the parts including the Allen head hardware? My belt squeals at start up and have tightened the alternator belt numerous times and it squeaks again a few days later. So the fact that adjusting that one and it goes quiet makes me thinks it’s not the others. Good idea to knock out a water pump while in there? Not leaking atm. The head not coming off is a relief.

 

I can’t help you on what a fair price would be to pay someone. I do all my own work so I’m not familiar with what shop rates are these days. As to the water pump, that’s your call, the original could last years or it could go within months of doing the oil pump, nobody knows, but while all the belts are off, it would definitely be worth considering. Especially if it has higher mileage. Another thing to have your guy look at is the balancer/crank pulley while it’s off. It’s not uncommon for the rubber to separate from the outer pulley allowing it to slip.

 

Thanks for your advice. I’ll be sure to post an update.

 

With the belt slipping your harmonic balancer is probably wearing out as said.

There's also a seal that it seats on in the timing cover and it can be the source of an oil leak all by itself....
so that should be replaced while everything is apart....

If that harmonic balancer wobbles too much for too long I've seen it crack the inside of the timing cover ....
right around the oil pump.....very hard to detect.....



This is kind of a tedious job...a bungling idiot could do some damage.....necessitating a future return...

sometimes getting those 9 screws out of the cover.....can be like summiting...
.....pb blaster.....torch.....hand impact drive......and prayer.....

 

Enough room for a hammer for the impact screwdriver with radiator? Or should I invest in an impact drill? Any way to verify replacement of harmonic balancer? Those aren’t that cheap

 

Yeah its a tight fit......got to pull radiator....
think I used a head off a 4lb sledge......

I watched several vids on strategies....

I have a micro torch and pb blaster( DeepCreep).....and I go very slow and careful...



There is no shortage of 4Runner and taco how to videos......




I have one of these.....but risky on those for sure....

 

And yeah I think I paid around $130 for a doorman HB one 4 yrs ago...

be super careful when you restab that and dont mess up the crank key, or the key slot...
either of which can destroy a crank shaft.....

make damn sure your perfectly in that slot before you crank the crank bolt down......

 

And secret to those screws is get the correct phillips bit for the impact...
need several to choose.....because its got to fit like a glove.....its a JIS....Japanese industrial standard...

7 of those will come out without any problem.....


Even the allen ones I'd be weary of......after years on a hot motor....I'd still pre soak and micro torch.....

 

I guess I’m wondering if throwing $160 (Dorman price now) at something I’m not sure is even broken is worth it. I have no idea when the belts were installed. May cross fingers and replace all 3 when reassembling. There is a seal behind the pump? And on the cover on the other side in front ? And gasket that covers the perimeter of the cover ? Maybe I’ll look for a diagram

 

I got all but one of the screws out with my ridgid electric impact driver without removing the radiator. Like mentioned a good fitting bit is key. For the last one since I was replacing the oil pump cover anyways, I just pried out on the cover until it broke off leaving just the screw in the timing cover which I could then just turn out with my fingers since it had no pressure on it. Another thing to note when reinstalling the balancer, aside from the key way in the crank there are two flats on the outside of the balancer that index into the pump itself, so you gotta make sure it’s seated all the way into the pump and keyway before torquing the bolt down.

 

The seal that rides on the balancer is in the oil pump cover itself, so it’s easy enough to install on the bench into the cover, then install the pump cover onto the timing cover which has a molded o ring seal.

 

there's videos on garage mechs that use a seal saver if the lip seal on the HB is worn as a safety measure....
if there's wear on the old HB where it seals....the new seal will fail in short order......the rear axle seals are very prone to this.....

this is where this job can go bad.....

so in theory a new seal and a new HB would be awesome....

and that big ass bolt is supposed to be replaced......
......me thinks thats BS and a waste of money.....

so I saved you $10.....and cost you $175 w/tax....

 

I really think the HB is like the lower ball joints.....

if those go out......the whole shuttle could explode.....


cost u a big chunk of change.....either way...

 

Also you know your suppose to load the oil pump vains with vaseline.....
and after filling motor with oil ....dry crank it(crank sensor unplugged) until the oil light goes off.....

Again videos out there.....make sure you check em out....