Piston Ring Replacement.

[akbyrner92]

Hey guys, I haven't been on here in quite a while (probably about 6 months) but I was wondering if any of you had some information. Ever since I got my car, it's had an oil leak. It started out with just black specks on the back of my car and my having to add about a quart in between each fill up. Now, I'm practically pissing oil. Having to add almost 4 quarts every other week and the back of my beautiful blue car is almost a charcoal color. I've narrowed it down to my piston rings, considering that's pretty much the only thing that could be causing what's going on. I've got a friend that I used to work on cars with, we're going to pull the engine when I come home for the summer.

So my question is, what all is involved in the ring replacement procedure (besides the rings, of course) is there anything else that I should do while I've got the engine out and apart and about how much would all this cost me.

On a side note, I did a forum search to see if I could bring anything up but I didn't find anything. However, if there was something completely obvious that I totally missed, a link would be greatly appreciated. Thanks everyone!

 

[RunAroundNekid]

Piston rings will NOT leak oil externally.
Ring replacement is a very involving job, and quite honestly, if you don't know how deep it goes, you should not even think of attempting it. You'll basically be rebuilding the engine, and having to replace the rings, bearings (do you know how to measure your bearing clearances, torque the bolts in the proper order and sequence, etc.?)
Get the car to a shop, and have them professionally evaluate it.
If its an internal oil leak coming through the exhaust, you should also look into valve seals.

 

[akbyrner92]

Well, the reason I pinned it as a piston ring leak is because after scouring the internet for a day and a half, that seems like it's a pretty common problem with our cars. Also, when the car was in the shop for something completely unrelated that mechanic told me about how Mazda had this same issue in the 80's with some of the b-series engines.

And the guy that will be helping me out has been doing this for 10+ years and he's actually in the process of rebuilding an engine right now. So I would hope he knows what he's doing

 

[95blkprobe]

blown piston rings isnt that common of a thing for the fsde. does it smoke at startup or when it has load put on it? you dont necessarily have to replace the rod bearings but it is a good idea. there is no special torque sequence you will need to take the rods out of the bottom of the motor. rehoning the cylinder walls would be a good idea since you are replacing the rings.

 

[akbyrner92]

Yes, it smokes BADDD on cold startups and when I really stomp on it (between 4.5k and 5.5K RPMs). I'll also be removing the VICS (or VTCS, I forget which of the two our engines has) while I've got it all out and apart.

 

[95blkprobe]

well theres actually no need to really remove the motor and all out of the car if you dont want to. you can drop the pan, seperate the tranny and motor to get the 2 hidden upper girdle bolts then after dropping the girdle plate, you will have access to the rod bolts. loosen the rod bolts and slide the rod and pistons out of the bottom of the motor, replace rings after gapping them correctly, use a bead style honer that you attach to a drill, blow everything out with compressed air then reassemble with asssembly lube and new rod bearings.

 

[akbyrner92]

That's quite possibly the best advice I've ever received. And honestly, I'd probably do it that way if it weren't for the fact that I have to remove the head to get to the VICS. That rattle is annoying the F*** out of me.

 

[CheeseHelmet]

That's quite possibly the best advice I've ever received. And honestly, I'd probably do it that way if it weren't for the fact that I have to remove the head to get to the VICS. That rattle is annoying the F*** out of me.

You don't have to remove the head to get to the VICS butterflies, they're built into the intake manifold. That being said, you probably don't want to remove them as you might lose some performance at low RPM. Furthermore, the most common rattle is caused by the VTCS system (which can be safely removed), see this TSB for more info: http://www.protegefaq.net/tsb/01-004-03.html

 

[akbyrner92]

Ok, so it is the VTCS. Like I said earlier, I couldn't remember which our cars had. Thanks for the link!

 

[neilv]

on start up and heavy acceleration is valve guide seals. wont be piston rings in your case. you only need to take the head off and get those changed

 

[RunAroundNekid]

well theres actually no need to really remove the motor and all out of the car if you dont want to. you can drop the pan, seperate the tranny and motor to get the 2 hidden upper girdle bolts then after dropping the girdle plate, you will have access to the rod bolts. loosen the rod bolts and slide the rod and pistons out of the bottom of the motor, replace rings after gapping them correctly, use a bead style honer that you attach to a drill, blow everything out with compressed air then reassemble with asssembly lube and new rod bearings.

No no no no no no no.

You can not just simply replace the rod bearings. You'll need to have the crank checked for scoring damage, then if the crank is good you'll have to measure the bearings clearances and have the crank machined to match the bearings.
You can not just slap it all together like this guy said, if you do, then 3 days later you'll be pulling it all down again.

Here is a GREAT write up on proper do's & don'ts when doing internal engine work. Please read it. I'd hate to see you doing it twice.

http://www.mustangandfords.com/techarticles/mufp_0610_engine_building_mistakes/connecting_rod.html

If you're interested, I build engines all day long at work. I work for an import performance shop called Gorilla Race Engineering in New Orleans, LA.
PM me and I can give you a quote to completely rebuild that engine for you. I can work with your budget, and do either an OEM spec rebuild, or a forged rotating assembly.
Lastly, valve seals can be done with the head still attached. Remove the valve cover and front timing cover components. Leave the timing belt installed and rotate the engine to its TDC (Top Dead Center) for cylinder one. All intake and exhaust valves should be closed. Now, remove the timing belt and camshafts. Using a cylinder leakdown tester, regulate the inlet pressure to roughly 15-20psi. Using the appropriate tool, remove the valve spring keeper and DON'T LOSE THE KEEPERS. Remove the valve spring, and then the seal.
Replace the 4 seals for that cylinder, then the cams and timing belt, and rotate the engine over to its TDC for cylinder #2, and repeat that step.

More often then not, burning oil is worn valve seals, unless you have something else major like a cracked oil galley in the head or block, but thats very, very rare.


Fyi, I don't want to come off as rude, or abrasive, I just want to see you fix the car right, the first time, and get back to driving it.

 

[CheeseHelmet]

Fyi, I don't want to come off as rude, or abrasive, I just want to see you fix the car right, the first time, and get back to driving it.

That's not rude at all, it's solid advice from someone who actually knows what they're doing

 

[95blkprobe]

If the bearing isn't chewed up or doesn't show any signs of wear, then the crank journals wont have any signs of wear as well. The bearing material is softer than the forged crank so you could obviously tell if there was an unhappy bearing in there.

Btw, I know what I am doing as well. Be careful who you call out like that since you don't know people in person and who they really are. Since you "work at a performance shop", that doesn't make you an expert engine builder either.

 

[flash75]

95blkprobe, would you tell us how you get the pistons and rods out from the bottom of the engine?
I'm sure they will not come out with the crankshaft in place. There isn't much spacing between
Mazda cylinders? Surely the main bearing webs are wider than the spacing between cylinder bores?

Even if you get them out how do you compress the rings to reinstall the pistons?

I have looked at many cylinder blocks and don't recall ever seeing one that permitted removal of
the pistons from the bottom. The exception would be engines with cylinders bolting to the
crankcase, VW for example. I do have some experience building engines including V8's, six, four
and single cylinder engines.

Clifton