Crankshaft front main seal leak?

[P-rev]

pic1IMG_20150327_203618_581.jpgpic2IMG_20150327_203844_548.jpgpic3IMG_20150327_203933_653.jpgpic4IMG_20150327_203718_138.jpgpic5IMG_20150327_204055_622.jpg

I took these photos earlier today of a '95 alltrac s/c I've been working on. I suspect the front crankshaft oil seal is leaking terribly. I bought this van sight unseen knowing it had some problems (she hit a deer). I took care of all the 'knowns', did some maint to be on the safe side like changing oil, coolant, plugs wires cap and rotor. I plan on changing the other fluids, but wanted to drive it a little first. Fired it up and oil began dripping from the bottom of the support strut shown in pic 5. A second trickle fell off the left bolt of the oil pump, shown in pic2. Looking closely at pic2 reveals oil dripping from the right bolt too, while the 'center-right' bolt appears 'clean' even though it's definitely not dry. It's wet (and I'm not sure what that wetness is).

In the other photos I'm trying to show the heavy caked oil on the block, all around the crankshaft and on the bottom of the oilpan, tranny... pretty much from the front of the block on back. I thought at one point it could be the head gasket, but the head is pretty dry and oil free. There seems to be a peculiar line actually where the head is relatively clean, but the block is caked with sluggy oil.

In pic3 a different angle of the bottom of the oil pump shows a 'shadow' of where the oil didn't appear to have deposited. This only makes me feel more certain about the front seal being the culprit.

I read a thread on another forum where a guy was replacing his crankshaft front oil seal and actually broke the bolt off which temporarily held the driveshaft pulley in place while he 'loosened' the main bolt. FSM recommends torquing that main driveshaft pulley bolt to 192 ft lbs... and this van has been in the desert for many years before coming to me, so the nuts and bolts are pretty dry and hard to break loose.

After taking the front drive shaft back out (8 nuts and bolts) and disconnecting the SAD shaft from the driveshaft pulley and scooting it into the hole the missing drive shaft has created... I was going to squirt some penetrating oil on that bolt to soften things up for a few hours (days) before attempting to break it loose. Tips and insight on this one is appreciated. I've been to the boneyard three times, excited to have found a '95 there to pull parts from and, at this point... have spent days reading this forum!! Not complaining though as I think I've chosen the Previa as my most worthy steed... I'm just ready for it to be over for a little while.

[P-rev]

I've never opened one of these up before and the FSM is indicating a rear seal just behind? the front main seal. Should I replace that one as well? Thanks.

[TheMAN]

carefully take off the SADS, then you can remove the crank pulley like any other engine and replace the seal
the SADS can stay in the van, you don't have to take it out.. you just have to unbolt both ends and move it out of the way

[P-rev]

Here is a comment I pulled from another thread regarding the crankshaft seal… which begins my growing concern...


-from pdgizwiz-
I believe that seal is part number 90311-48014. It’s pressed into the oil pump cover.

The big weird O-ring under the oil pump cover is 15188-76040
There is also a figure-8 shaped O-ring under the oil filter housing, and it’s p/n 15692-76010.
All of these are made of 20+ year old rubber, which is no longer very rubber-like and is prone to cracking. Once it cracks, it leaks.
If you manage to remove the mega-bolt that holds the front pulley onto the crankshaft, the hard part is over. You’ll have to lock the crankshaft some way. There’s the rope trick, but I’ve not done this with the engine in the van, so there may be a better way that someone with experience might suggest.
The oil pump cover is held on with a bunch of flat-head screws and you MUST use a JIS bit to get them off or you WILL bugger them. I bought this for my old impact driver set, and it works great:
http://www.vesseltools.com/hand-tool...ct/431801.html
It also makes it possible to torque the screws back down, too, with an 8mm socket.


The short of it is, I'm a little confused now. In my inexperience I was hoping to get away with just replacing the crankshaft seal, but it seems like I should also replace 1) the timing chain cover gasket? 2) oil pump cover gasket 3) a seal directly behind the front main crankshaft seal the FSM shows, but parts suppliers are unfamiliar with…

Along with tricky screws for the oil pump cover is the delicate measure of securing the crankshaft somehow (which I'm not keen on) while breaking loose the main nut which I know is REALLY on there. I don't really want to drop the motor if I can get away with it. I'm sure it's going to be tough popping that crank nut loose. If anyone has tips on this I greatly value your wisdom!

[TheMAN]

I'm sure you can take off that bolt using an impact wrench

[pdgizwiz]

There is no seal "behind" the seal in the oil pump cover. Forget that. Don't trouble yourself with the front cover gasket. That would be a nightmare with the engine in the car - maybe impossible. Save that for the engine rebuild someday.
I expect that theMAN is correct in that a pneumatic impact wrench would make quick work of the big nut, but working in an apartment complex this may not be an option.
Are you familiar with the "rope trick"? I did this on a Subaru once and proved the principle. I can explain or you can google it.
You could skip the seal under the oil pump cover, but like I said, if you get the pulley off, and have a JIS bit in a hand impact driver, the rest is easy. I've changed a few of the seals now, and every old one I've removed has come out in pieces. The one under the oil filter housing is a breeze.

[timsrv]

I haven't tried this on a Previa before, but this redneck method should work on Previas too .

[TheMAN]

yes, you can take it off that way, but how are you going to put it back on?

[timsrv]

Hook the starter up reverse polarity? .

[pdgizwiz]

Rope trick!

This will work on any engine if done right.
Important bits missed by this brief video: Do this on a cylinder that is on its compression stroke, so that you don't run the risk of bending valves. Get enough rope in that the piston stops about halfway up through its stroke, so that the leverage through the crank is maximized.

As the spark plugs are down a long tube, and it isn't easy to "push a rope", I found I needed to find a plastic tube with a small enough ID to get the rope to feed into the combustion chamber instead of just wadding up in the spark plug tube. And not every rope will work, obviously, it needs to be stiff enough to "push" and be relatively incompressible once in place, yet flexible enough to coil up on top of the piston as it enters the cylinder.

I did this with a Subaru once. Whoever had done the timing belt last had not gotten the pulley nut tight, and it came loose, destroying the keyway on the pulley. I had to replace the pulley and re-torque the bolt so that it didn't happen again. I'm sure there is a way to lock the torque converter, but didn't have any kind of special Subaru tool to do that.
I have a tool that I made eons ago for VW bug engines that I'd use to hold a flywheel while tightening the big nut that held them on. I've used the same tool on other engines to remove or torque damper pulley nuts, but the engine has to be out of the car to expose the flywheel or flex disk on the back of the crank.

[P-rev]

I got a chain wrench from Harbor Freight, luckiy there's a store not far from my house. Also got a torque wrench with 550 ft-lbs of torque. It finally came loose after 15-20 minutes of "impactful persuasion" and several different configurations and impacts/breaker bars. Now the fun part begins! Went with the Toyota seal and am leaving it at that... for now. I will update when she's all back together and driving. Thanks again for this great resource!

[P-rev]

I haven't tried this on a Previa before, but this redneck method should work on Previas too .

Tim great suggestion, but being I was working under the van most of the time my neck didn't get that red


Update:

I got the crank seal in fine, but it seems I didn't quite go deep enough. In hindsight I would've replaced the oil filter housing gasket as well as the oil pump cover gasket. Impatience grew and I just wanted to get out from underneath the van. After I got it back together, noticed oil was still leaking so I (with dwindling patience) pre-cleaned and applied some FIPG over where the leak was happening and it's all but stopped now. The motor has 300k miles and... I had to draw the line somewhere. I'm looking forward to rebuilding it (at some point) and it just seemed like if I got too much deeper I should drop the motor/tranny.

Anyway, after that I took it out for a test drive and noticed a 'pulsing' in the drivetrain. The passenger's CV shaft boots were both pretty torn up and the joint itself was popping and cracking a bit. Swapped it out and noticed the two flexible brake hoses are rather rotten looking. I haven't taken her out for a test drive of the CV shaft, wanted to get the brake hoses put on first. So... they're on order. I might just pop the tire back on and take it out for a spin today and hopefully this will be it for awhile and I can start driving 'er!

Thanks again for all the helpful resources and wisdom on this forum. Totally invaluable for a mechanic such as myself.

[P-rev]

Well, the new CV shaft works great, but I think it might be the tranny Not positive, but the noise/vibration (mechanical sound) still very much present and I don't really want to drive it very far. My other Previa, the '93, just blew a head gasket yesterday so I'm hoping to bring up my batting average real soon. This 'project' is becoming a real saga... I thought it could've been the front drive line as I had removed it to get the SADS out but didn't put matchmarks on it. I rotated it a couple times with no noticeable differences.

My question is, do the non s/c and s/c models have interchangeable trannys? I'm looking for a trans shop north of Seattle at the moment. Wisdom is appreciated. Thanks y'all.

[pdgizwiz]

My question is, do the non s/c and s/c models have interchangeable trannys? I'm looking for a trans shop north of Seattle at the moment. Wisdom is appreciated. Thanks y'all.

I believe the transmissions on the sc and na models are different. I don't know the model numbers by heart, but Toyota put a beefier one behind the supercharged engine. Even if they are mechanically replaceable I'd be surprised if the electrical connections match up. I'm not speaking from first-hand knowledge, though so hopefully someone else can confirm or correct me.

[Noel]

My question is, do the non s/c and s/c models have interchangeable trannys? I'm looking for a trans shop north of Seattle at the moment. Wisdom is appreciated. Thanks y'all.

Check these guys out: http://www.garagetunerautomotive.com/ I'm really bummed that I found out about them AFTER moving away from Seattle.

[TheMAN]

physically interchangeable between S/C and non-S/C trans... but it won't work because the electronics are very different and the ECU won't know how to control it properly
they are completely different transmissions in other words... non-S/C similar to the one used on the mid to late 80s cressida, the S/C similar to the mini-trucks/4-runner V6 one

[maestro123]

For the JIS bits to take off the oil pump cover, I bought a set from this website:

http://www.phonetechsupply.com/produ...set-2400-2500/

It appears to be some phone technician supply site. Vessel tools wanted to charge me $13 for shipping which was price gouging for a bit set. Phonetechsupply charged me $3 for shipping.

Also, I tried using a 1/2" impact gun for taking off the crankshaft bolt. Didn't work for me. After a while, I went ahead and tried the starter bump method, and PRESTO!, it was off.