Cracked Oil Pan to go along with my warped Head!

[Jester]

So I'm in the middle of 1FZ hell right now. Short story is my '97 40th with 130K had a water pump fail and overheated from lack of coolant. I pulled the head to change the HG because I knew it was inevitable. (Yep, the #6 fire ring looked like everyone elses.) Machine shop called yesterday to tell me my head was warped 0.017 in! I went by the shop today and confirmed it with my own eyes. They offered me an option of sending the head to a shop in Florida to put it in an oven and try to straighten it, but I choose to just order a new head from my new best friend, cruiserdan. (Seriously - Dan is the best. Not sure how I'd get through this without him and this board to lurk on.) Cost of the new head was not much more than what it would cost to try to fix my old one.

In addition to the head, I pulled the oilpans and the timing cover. I had an oilslick under the 80 after the overheating and I needed to determine where it came from. I've yet to determine for sure, but it seems like all the normal stuff (front seal, pan arches & oil pump cover) may have been contributing. I still need to confirm all the oil galley plugs are where they belong.

Tonight I was taking it easy and cleaning up some parts and saw a crack. I didn't notice it during the hours I spent cleaning the pan , but when I put a thin coat of "Alumablast" on it it jumped out at me to make my bad day complete. Question is, is it a problem? Seems to me that Toyota intended for this oil pan to be a structural part of the engine as they put 6 big freaking bolts from the transmission into it. The crack isn't in a spot where I will loose oil out of the crankcase though. Had I not painted it, I don't think I would have ever known it was there.

So far, I've dropped close to $2K in parts in this repair and i'ts not back together yet. Its amazing what you find to replace "While you are in there". When I get all done, I may try to write it all up - it has been an adventure so far. My wife wants her truck back yesterday, and I'm still finding stuff wrong.

So what do you guys think about this pan crack? Replace it? (I hate to think what that would cost) Try to weld it? Let it ride as is?

[cruiserdan]

That is a BITE!......


You need to fix it or replace the pan. It will grow if you don't. You may be able to find a used pan. You will need a 95 up piece... If it were mine I would prefer a different pan but if the machinist thinks it can be repaired that would be the least expensive route.

[Wrench]

Weld It!

[Cattledog]

Drill it and have it welded. Any chance the block is cracked?... I am surprised to see the pan cracked.

[IdahoDoug]

Take it to a shop - a good shop. Whomever you're using may not fit this category as I'm surprised they'd have to ship it from NH to freakin' Florida to have a head straightened. My local shop had someone in town who can heat and straighten aluminum heads. After getting it closer to tolerance (say .005) then they machine it flat.

At a good shop, you could get an evaluation as to if welding it would work. My shop (very good) sent my aluminum head to a local specialist who heated it in an oven and welded it. Your crack looks WAY easier to weld as it's completely accessible from both sides - should be simple.

So, questioning the "ship the head across country" deal and also suggesting this is an easy weld.

DougM

[cruiserdan]

He opted to go with a new head.

[IdahoDoug]

Yeah, got that he decided to get a new one. I was just pointing out that their expertise might be in question in terms of having them decide on what to do about the oil pan if the best they could do on straightening a head was sending it across the country. Based on this single data point they're not a good authority to evaluate this second issue, but a good shop would be.

DougM

[landtank]

Drill a 1/8" hole just beyond the end of the crack to stop it's growth and bolt it back up. The crack is actually below the structural support ribs of the pan.

[Cattledog]

Doug, I don't think Jester lives in NH. I do though. I can understand the shop sending the work out to a known "good" shop. Shipping is cheap compared to poor/improper/unkown work.

Welding that cast pan looks like no big deal. But, if I had dropped $2K+ on an over heated engine in parts alone, I would have the block checked for cracks. Who would want to rebuild it twice.

[Jester]

Yep, I'm in Virginia - Not NH.

I've been looking for a good machine shop for some time in the area. I think where me head went is a good one, as they mainly do race car work. I was very impressed with how clean the shop was. Just because they don't an head straighteing oven it doesn't mean they don't know what they are doing. I had never even heard of the procedure until they mentioned it to me. I chose to go with a new head because the cost I was quoted to fix my old one was $915 (which was all going to the shop in FL... Clearwater I think) and I had never heard of the procedure before. Perhaps it is more common than I thought, and would have been fine, but I know that a new head (even though it cost a little more) will fix many of my problems. I will still need to get my old valves ground and put into the head which I think is going to run me another $150.

I hope the oil pan crack wasn't heat related, but something caused it at some point in its life. I've only had the truck for the last 30K and my wife has done most of the miles hauling our dogs to shows. Cruiserparts.net shows used FZJ oil pans for $100 and I've sent them an email. Sounds like I might be able to get my old one fixed for less if I find the right person to do the work or do it myself (I can't weld aluminum yet, but I can drill holes!).

You guys are scaring the crap out of me with mentions of a cracked block. I was staring at it last night and realized that only 4 bellhousing bolts and 6 torque converter bolts is all that is keeping the engine from sitting on a nice accessible stand for closer inspection and reassembly. The FSM instructs you to pull the block and tranny together, and I can see it being a real bear to get the top bellhousing bolts in with the head and intake on. Has anyone ever done this successfully? Are there common areas where a 1FZ will crack or do you think I need to take it somewhere and magnaflux it?

I am so bummed right now.

[Jester]

Here are some more pics of the project.

[94landcruiser]

I had my BMW 325's aluminum oil pan welded 2x (it is the lowest part of the car, thanks BMW) for 60.00 and it has been fine (until I bottomed it again)

[landtank]

It's an IRON block not an aluminum oil pan, I wouldn't sweat a crack in there. That crack is in an area arohnd the inspection cover, I wouldn't sweat that as well.

[Jester]

Another...

[Cattledog]

Landtank has a good point the block is made from a high quality iron alloy and unlikely to be cracked. I am just surprised by the pan fracture.

IMO, I would have the block checked if I was spending $2K+, and had only a couple of dozen bolts left to pull. I would not want to spend that type of money or specifically time twice on the repairs. Personal choice.

I wonder if reinstalling the head and pan would be easier on a stand than in the truck.

[Jester]

I decided to try to repair my existing pan. First I drilled through the casting past the crack and then smacked it with a hammer to make the crack grow to the hole. Then I v-grooved it with a Dremel, bead blasted the area, and washed it with Acetone.

[Jester]

I took the pan to work and got some bead laid on it with a spool gun. I would have rather TIG'd it, but the spool gun and a guy who knew how to use it was available. After I filed the machined surface flat I found a lot of voids in the weld. I chased most of them down with the dremel. I think it will okay. The crack itself still baffles me - I don't think it was caused by the overheating or some sort stress, but rather a manufacturing flaw or somebody (not me) either dropping it or prying on it without all the bolts out.

I should have a very large order arriving from American Toyota tomorrow, including a brand new cylinder head. Looks like my weekend will be busy.

[concretejungle]

Interesting. I think TIG would have been the way to go also, but this fix may work just fine. Time will tell.

[elmariachi]

First off, cheers to you for tearing into it like that. Most people would have puked up their dinner after finding that crack. I think you are in good shape with it now. Just take your time and get it all back together and go on. Good job!

[rockclmbr]

Jester,

How did you get that so clean?? Did you sandblast the entire pan?? Looks nice, and excellent repair!

[Jester]

Originally Posted by rockclmbr

Jester,

How did you get that so clean?? Did you sandblast the entire pan?? Looks nice, and excellent repair!

Well, when the 80 went down and I knew I had some major repairs to do, I invested in a 40 gallon parts washer. A 3:1 mixture of water and concentrated Simple Green went into the tank. The oil pan spent about 4 days in there with a hot water rinse and scrub each night. I did glass bead the area where the weld was made, but the pan mostly came clean in the degreaser. I've spent a lot of time rinsing the pan with air and water to be sure I got all the abrasive out. A very thin coat of "Alumiblast" (a quick drying paint with aluminum in it) was applied to keep it looking good. Ironically, it was not until the Alumiblast went on that I noticed the crack as the paint was sucked into it - kind of like a poor mans magnaflux for non ferrus parts.

[Jester]

Got a shipment from American Toyota today...

[IdahoDoug]

Wow. That's a gorgeous hunk o' high end alloy. It's cruiser porn.

Is there a process to mate the cam journals with your worn-in camshaft or is it assumed that the clearances are correct? In other words, will you plasti-gage the journals or is this just a bolt it together deal by the machine shop?

DougM

[mickey_rubicon]

at 220k with a noisy water pump bearing, this thread makes ma all paranoid all over - arghhh maybe I will do the water pump before it dies, ...

[Jester]

Originally Posted by IdahoDoug

Is there a process to mate the cam journals with your worn-in camshaft or is it assumed that the clearances are correct? In other words, will you plasti-gage the journals or is this just a bolt it together deal by the machine shop?

DougM

Doug,

That is a great question. My assumption is that most of the wear is on the aluminum cam journals and not the steel camshafts. The new head came with matched journals installed on it. I suspect that if I were to plasti-gage the old head and cams I would find more clearance than I would with the new head and the same cams. The FSM describes how to check the camshaft journal oil clearance and the camshaft thrust clearance and gives both a normal range and a maximum clearance. If it is found to be above maximum, replacement of the camshaft and/or bearing cap & cylinder head are the recommended action. I suspect that with my new head & bearing caps I will be in the correct range with my old cams, but I am taking everything to the machine shop for them to check out. As far as breaking in the old cams to the new journals I'm not sure what I can do other than putting some good assembly lube on there and change the oil very soon.

[Jester]

I'm know I am suffering from a case of "While you are in there..." syndrome, but I had to replace the power steering cooler when I saw the corrosion on it. Toyota didn't put a great finish on it to protect it from east coast road salt. Seemed like the time to fix it.

[Jester]

I put this together to keep the valve train components organized.