Replacement engine

[Fireman]

Got the engine on the stand and started tearing into it today.

Obviously hadn't been using the highest quality oil. Lots of solids in the oil pan.

Pulled the #1 rod bearing expecting to find carnage but it was clean. Went ahead and plasti-gauged all of the rod bearings and found them all to have clearance of .002 and slightly under.

The only damage was a slight groove on #4 rod bearing.

And of course I had to break a sensor as I pulled them. #4 in this picture. Dammit!

I'll tear into it further on Wed. I'll check the main bearings with plasti-gauge and then onto pulling the head.

 

[Fireman]

Quick question: When I plastic gauged the rod bearings, I only torqued them to the specified 35 lbs but didn't do the extra 90* turn. I know that if it had any effect, that it would just show the tolerances to be closer. Does anyone think that it would have made any difference?

 

[Fireman]

Crank bearings all .002-.003 so well within specs. Good news so off comes the head!

White Trash of the Elwood Chapter, TORC4x4.org, Cottonland Cruisers.

 

[Fireman]

Hopefully something will show up soon as to what was causing the knock. I did see where one member had problems with the drive gears on the crankshaft. Is there anything associated with the timing chain that might be responsible for a knock that increases with RPM? Really sounded like a rod except it didn't have that double knock (at the top and bottom of the piston stroke), it was more just a single knock per revolution.

 

[Pin_Head]

The power steering pump and oil pump gears are often the source of knocking noise. There are several threads on this, so try an advanced search on knock and power steering.

 

[Fireman]

Cool, I've read some about them. Will do a thorough inspection of them when I get the timing chain cover off.

 

[Pin_Head]

In the most recent thread there was no obvious physical damage or wear, but replacing the gears made the knock go away. It is useful to be able to test it while the engine is running by temporarily removing the PS pump or loosening the crank pulley nut and seeing if the noise goes away. The crank gear drives the oil pump, so you don't want to run it for long with the nut loose.

There is also an axial thrust clearance (front to back) for the oil pump gear and the timing chain cover listed in the FSM and how to check the gap.

 

[Fireman]

I really wish that I would have tried to diagnosis a little further instead of just pulling the engine. I was under the assumption from the information given to me by the previous owner that his mechanic had diagnosed it down to a rod knocking on Number 1 cylinder

White Trash of the Elwood Chapter, TORC4x4.org, Cottonland Cruisers.

 

[Fireman]

Got the cans pulled but since it was Valentines day I didn't get any further. Got bored at the station and cleaned the cam bearing caps.





White Trash of the Elwood Chapter, TORC4x4.org, Cottonland Cruisers.

 

[Fireman]

Got the head gasket off tonight and it looked to be in pretty good shape for 200k.

Timing chain cover off and all seemed good.

Started inspecting the cylinders and all looked good except #1 and #6.

#6

#1

Went ahead and pulled the pistons in those two

#6

AND #1 Oh crap!

Cylinder wall #1

I'll pull the rest and then get the micrometer out and check the cylinder walls for out of round and size.

At least I found the problem.

 

[Bodean]

You just gonna build that one David?

 

[Fireman]

Not sure yet. Pulled the rest and found #3 had some scarring also. They left some piston material on the cylinder walls that I was able to get off and when we have a pretty day that I am off from the station we will hone it and check it with the micrometer. The bearings just looked so good on this one that I am going to wait till I tear into the other motor.

 

[Fireman]

Took a while but we finally got around to using the ridge reamer on it and honing it. Bad news, a bore job on this block will be necessary to clean it up. I just did the #1 cylinder but there was still a strange ring groove showing up by sight and feel. You could also see the discolorization from where the motor got hot. On to the next block! And replace the ring and pinion and bumper on my 4runner crawler before Roundup.

White Trash of the Elwood Chapter, TORC4x4.org, Cottonland Cruisers.

 

[Fireman]

Well I finally tore the other engine down and all looks good. A lot cleaner than the first one and no visible damage. All the bearings were well within spec and no ridge on the cylinder walls. Now to hone it and check the bore size. A little good news I guess.

 

[SierraMtns]

Great thread. Thanks for posting. Its nice to see a stock motor going back in.

 

[Fireman]

Thanks, we will be traveling in this one and I want to keep it as reliable and simple to work on as possible. And since my wife will be driving it more than me, it doesn't need to be a hot rod or a grease burner!

 

[Fireman]

Motor is completely torn down and the only unusual thing so far is the amount of crude in the coolant side of the oil cooler. Going to pull it apart and give it a good cleaning before reassembling.

 

[Fireman]

Purty!









White Trash of the Elwood Chapter, TORC4x4.org, Cottonland Cruisers.

 

[Fireman]

One quick note while I am thinking about it. A good friend of mine who is a Toyota mechanic gave me a tip on pulling the head. He told me to check all of the valve clearances and record them while keeping the valve buckets and shims organized so that when you are reassembling them, if you don't have to change any valves, you can have a pretty good idea of what shims need to be adjusted.

 

[94SRUNNER]

Looking good!