My '97 Maintenance and Transformation Thread

[subzali]

BVSV - it blocks vacuum when cold, and then when the coolant temperature reaches a certain temp the bimetal disc pops open and allows vacuum to pass through.

 

[jdeitch]

I know I am kid of late to the game and haven't read the whole thread yet, but the top of that piston looks like it was running lean, hot or pinging. Did you get the numbers back from your injectors did you have one with a bad flow before they were fixed? I would definitely replace it while you are this far into the motor, I could see that piston cautostophically failing if leaving it the way that it is.

Look at the valves... Possible water in the cylinder?

 

[Wheelingnoob]

That defiantly looks like FOD (Foreign Object Damage), that would also explain why the inside of your head look like new, I have never see the inside of a head look that clean on an engine with 1/2 the miles.

I would replace that piston and hone and re ring all cylinders.

 

[dranven]

Ugh. Well, I'm at the point of no return. The no. 1 oil pan is ready to go back on. All these differing opinions, "replace the piston and rering everything", "leave it alone". What's a guy like me to do?

From what I understand, I can't rering all cylinders reusing the same old pistons. If that's true, then I would have to replace all pistons.

 

[dranven]

Well, I pulled the no. 6 piston out. Here are more photos.

 

[Schwaz80]

I'm not a mechanic, but that can't be good.

 

[OGBeno]

Looks like it's time to put a call into the parts shaman (CDan) for block parts.

 

[Kernal]

Not a piston damage expert but IMHO the photos in post #85 almost look like the top of the piston melted then flowed over the edge a bit but was stopped by the cylinder wall??

Any updates?

 

[dranven]

Not a piston damage expert but IMHO the photos in post #85 almost look like the top of the piston melted then flowed over the edge a bit but was stopped by the cylinder wall??

Any updates?

I talked to a Toyota tech and a few locals and all are convinced it was foreign object damage. I got mixed opinions on replace vs. leave it alone, but in the end it scared me enough to replace it, "since I'm there".

New piston was ordered, along with a ring set. Flex hone is on the way and should be here by early next week, then the updates will continue! So basically, I'll be replacing the piston and reringing all cylinders. Rod bearings will be case by case, but the Toyota Master Tech saw my no. 6 bearings and said he would not bother to replace them. Good enough for me.

Updates to come.

 

[jdeitch]

I talked to a Toyota tech and a few locals and all are convinced it was foreign object damage. I got mixed opinions on replace vs. leave it alone, but in the end it scared me enough to replace it, "since I'm there".

New piston was ordered, along with a ring set. Flex hone is on the way and should be here by early next week, then the updates will continue! So basically, I'll be replacing the piston and reringing all cylinders. Rod bearings will be case by case, but the Toyota Master Tech saw my no. 6 bearings and said he would not bother to replace them. Good enough for me.

Updates to come.

Sounds like my option D

Keep the faith brother... You're doing fine.

Get some plasti-gauge and assembly lube. What size rings did you buy? Check FSM for specs on ring gap. check gap at top, middle and bottom of stroke. cylinders do NOT wear evenly. Either research how to carefully manually file the rings or buy/borrow a ring filing tool.



You might also check out the tool for installing the rings on the pistons. Not necessary but remember rings are very brittle and will break easily if mistreated. YouTube I'm sure has something on these topics.

You'll also need a ring compressor. I prefer the corrugated type as they will not try to enter the cylinder with the piston.



Make sure to properly offset the ring gaps when you reinstall the pistons. Put rubber hose over the connecting rod cap bolts to help guide them over the crank and to keep them from damaging the bearings.

I would measure your rod bearing clearance with the plasti-gauge on at least on connecting rod. Check readings in FSM to help determine amount of wear.

When honing the cylinders use regular motor oil and be careful to protect crank and ensure no grit/oil from honing gets on crank/bearings.

While the bead hone is spinning do not let it extend out of the cylinder top or bottom.

You can YouTube or call me again if you like. I deploy in 13 days and will be unreachable for awhile

 

[dontblink]

Sounds like my option D

Keep the faith brother... You're doing fine.

Get some plasti-gauge and assembly lube. What size rings did you buy? Check FSM for specs on ring gap. check gap at top, middle and bottom of stroke. cylinders do NOT wear evenly. Either research how to carefully manually file the rings or buy/borrow a ring filing tool.

View attachment 679322

You might also check out the tool for installing the rings on the pistons. Not necessary but remember rings are very brittle and will break easily if mistreated. YouTube I'm sure has something on these topics.

You'll also need a ring compressor. I prefer the corrugated type as they will not try to enter the cylinder with the piston.

View attachment 679323

Make sure to properly offset the ring gaps when you reinstall the pistons. Put rubber hose over the connecting rod cap bolts to help guide them over the crank and to keep them from damaging the bearings.

I would measure your rod bearing clearance with the plasti-gauge on at least on connecting rod. Check readings in FSM to help determine amount of wear.

When honing the cylinders use regular motor oil and be careful to protect crank and ensure no grit/oil from honing gets on crank/bearings.

While the bead hone is spinning do not let it extend out of the cylinder top or bottom.

You can YouTube or call me again if you like. I deploy in 13 days and will be unreachable for awhile

Thank you for your service.

 

[livinoffroad]

Whoops just discovered those are NOT fusible links. Thought I'd better double check and...they turn out to be just connectors. I wanted to post the correction, because I don't want to be posting mis-information. No wonder I never had any trouble with 'em.

OK so...a correction to my correction...I was right the first time.

In this thread: https://forum.ih8mud.com/80-series-tech/628669-fusible-link-97-lx450-fixed.html the fusible link is described as 3 SHORT PIECES OF WIRE between the battery terminal and the little connector box with the bolt/post in it, and the separate plug connector.

The 3, according to page BE-4 of the FSM, are the Main, AM1, and AM2.

I assume AM stands for "Auxiliary Main", correct me if I'm wrong.

These 3 pieces of wire have a specific melting point, and can be obtained in bulk, by gauge.

I would like to know what the gauges of each wire are, so I can make my own.

Of course, they can be ordered from Toyota for around $10. HTH

 

[dranven]

Sounds like my option D

Yup, option D it is. Thanks for all your help. I got the standard size ring set after measuring the bore at the 3.93 in.

I got the flex hone in, as well as the new piston and ring set.

And here's the no. 6 cylinder after honing. Hopefully it's good enough.

I will check the ring gap today. The Toyota Tech said I should not have to file at all if my bores measure up that close. I did some reading on it, so it I have to file, then I will, but we will see. I purchased a ring compressor, as well as a ring expander, so I will begin use of them today.

Also, just a note on the piston wrist pin. After removing the retaining rings, the pin was knocked right out with a hammer and wooden dowel. The new piston came with a new wrist pin, which did not go in as easily at first. The FSM calls for heating the piston before installing. Instead, I stuck the wrist pin in the freezer for about 45 mins. It went in pretty easily after that.

More updates today or tomorrow.

 

[TYM4FUN]

Also, just a note on the piston wrist pin. After removing the retaining rings, the pin was knocked right out with a hammer and wooden dowel. The new piston came with a new wrist pin, which did not go in as easily at first. The FSM calls for heating the piston before installing. Instead, I stuck the wrist pin in the freezer for about 45 mins. It went in pretty easily after that.

More updates today or tomorrow.

Nice ingenuity...

 

[blkprj80]

Dranven, it's hard to tell from your pic but it looks like you need more motion on the hone. I'd maybe do the other 5 cylinders and come back to #6 for a touch up.

Here's what mine looks like. It was done by a shop. Probably by a machine. But you get the idea for what it should look like.

You're coming along good. I'm still at square 0.1 on going back together. I hope to set the crankshaft tonight...

Keep up the updates. I enjoy watching you make progress. It keeps me motivated on mine as well.

Jim

 

[Kajun]

Subscribed. I have a 97 FZJ and may be doing this in the next year or two. I have no reference for power feel comparison but mine seems to be lacking in the umpf department.
This is good stuff.
Maybe I missed it in the thread, but what are you doing with the head? I know you sent it out, but what were the specifics of what was worked on?

 

[dranven]

Dranven, it's hard to tell from your pic but it looks like you need more motion on the hone. I'd maybe do the other 5 cylinders and come back to #6 for a touch up.

Thanks for the comment Jim. You're right. It does look too horizontal. I went over it again. What do you think?

 

[dranven]

Subscribed. I have a 97 FZJ and may be doing this in the next year or two. I have no reference for power feel comparison but mine seems to be lacking in the umpf department.
This is good stuff.
Maybe I missed it in the thread, but what are you doing with the head? I know you sent it out, but what were the specifics of what was worked on?

Yea, I took the head to a local shop and they cleaned it, surfaced it, and did a valve grind job, and of course replaced the valve stem seals (I provided the new seals to them).

I also had them stick a freeze plug into the EGR passage from where the exhaust manifold bolts up (so I can disable the EGR), but more on that later once I get to putting the head back on...

 

[dranven]

Well, got the new rings on no. 6 piston and stuck it back in. I should have snapped some photos, but was feeling lazy about it.

I also took out no. 2 and no. 5.

The bearings on no. 5 don't look too great, but what does Mud think?

No. 2 looks pretty good IMO.

 

[dranven]

Ok, well replacing no. 5 bearings and leaving no. 2 alone. On order.

Meanwhile, honed out no. 2 cylinder.

Note, I use a little yellow plug for the oil jet, and I put a large ziplock plasti bag to cover the crankshaft.

And here's the result of the honed cylinder no. 2.

Also cleaned piston no. 2. Looks pretty good, yea?

There is a little damage on the top, but not nearly as bad as no. 6.

Here are the bearings on no. 2, which I am keeping.

And here's piston no. 2 with the new rings.

Ring gap was measured at 0.014 for comp no. 1 ring and 0.023 for comp no. 2 ring for the no. 2 cylinder.

Here it is about to be put in.

Annnd, it's in.