I tried searching for a similar thread and found nothing. I apologize in advance if this question has been answered. I recently replaced my plugs because I had a hunch one of them was fouled. Sure enough it was. I am guessing this is due to a leaking piston ring. I am wondering if it is possible to remove the oil pan and drop them out the bottom of the motor on this engine. If so, is this a pretty straight-forward process and is there anything I should know in advance?

 

No. Not going to happen. Your gonna have to pull the heads.
You can pull them out the bottom, but how are you gonna get them back in? Time for a rebuild.

 

Not sure if you are 4WD or 2WD but if 2WD you have to take the engine out as the oil pan bends over the steering arms.

The rings are easy, can be done by hand but if you are going to pull the whole motor for the rings you are best of replacing the crank bearings, thrust bearings and rod bearings too...

PS the rings are easy to install and can be done by hand. Just make sure you put them on in the correct order with the appropriate side facing up on the 1st 2 rings. The bottom oil ring kinda/sorta looks like a chain and has a ring above and below it.

 

DO NOT put rings in only by hand. Please use a ring compressor at the very least. And preferably a ring separator tool as well. If you shove the pistons without compressing the rings your gonna damage the rings. And you really shouldn't just slap rings in either. Should be using a cyl hone to prep the cyl walls. As well as a ridge reamer. More thing that cannot be done from the bottom of the engine.

 

While the above post is correct, if you do have the ring tool, use it. I found it surprisingly easy to install my rings by hand, albeit I did break two of them by learning how NOT to do it..

 

At this point you don't even know If you even have a cracked piston....

 

It is a 4wd. I have access to all the necessary tools. It was a seasoned mechanic who suggested that it was possible. I have a pit to work in as well. I really don't want to rebuild a motor that is infamous for having recurring HG issues. It was already fixed once at 90k by toyota. It now has 190k, needs a new HG once again (I just dumped bluedevil in and it mostly worked) and they are refusing to do it again. I plan on dropping the 3.4 in this summer as time and finances allow. Just looking to get by and maybe learn something in the process. This is my daily driver and I need it to get to and from school until June. Thanks for the input!

 

If the piston is cracked, can I swap a new on in the process?

 

X2
Have you done a compression test yet?

 

A seasoned mechanic wouldn't even consider dropping pistons to replace rings without pulling heads off. Not one I'd want to be asking questions to anyway.

A compression check won't tell you a difference between a bad ring and a cracked piston. But a compression check coupled with a leak down check will tell you the difference between piston/ring and a valve. And a hole/crack in a piston will show up as if it's a bad valve unless your doing a real leak down with an air compressor.

 

Agreed, but just guessing (as he mentioned in his first post) won't tell you anything other than you are wasting time and money!

 

Just wait till summer then. Why are you worried about a little oil leak for now?

Either way thats a lot of work just to pull the motor later on to do a swap.

 

@ThatGuy- I'm burning through about 1.5-2qt of oil per week and it feels as if it already fouled the new plug I put in. i.e. it is way more sluggish than usual/starting to blow quite a bit of blue smoke while warming up. It is just all around irritating.

@xxxtreme22r- I miss spoke. He isn't a professional, but has worked on classic cars for a long time and is a friend who is trying to save me some time and money. I'll take your word for it though.

 

He did mention it was a less than ideal operation.

 

Ya that is alot of oil. But still, I wouldn't want to pull the motor twice in the same year

Definitely wouldn't do it from the bottom. 4wheel drive or not it would be a nightmare.

But if you tear into the top end you might as well do everything right. Id personally just deal with it for now and start on the parts for a 3.4

 

There are lots of ways to get oil into a cylinder (and onto your plug). Smoke "mostly" at first sometimes suggests a bad valve seal (oil leaks in while it's sitting, then burns off when you start it).

Or, you said you believed it needed a new head gasket. They fail lots of ways, including oil-to-cylinder.

I have a lot of respect for leak-down tests, but I don't think they can tell the difference between a broken ring, bad oil seal, and a bad HG -- all will leak into the oil passages.

I'm no expert, but I don't think you know enough to call "ring" yet.

If you have a plan to put in a 3.4, fixing this one seems short sighted. Except that you could be stranded by the side of the road before a whole lot longer.

Good luck!