Windstar Compression Test

[BubbaFL]

2002 Windstar, 146k on the clock. I've been chasing an intermittent misfire for a month or two. I've eliminated all of the usual (easy) suspects - plugs / wires / coil pack / vacuum leaks / EGR etc.

Just did a compression test, results are

#1 140
#2 140
#3 142
#4 140
#5 165
#6 80

What do you guys think - is it worth fixing?

I guess the next step is pull the head and look at the valves and gasket to try to find the problem? Or should I be pulling the engine and looking for a new one?

 

[TFB1]

If that is a consistent 80 psi it still should run fairly smoothly... Possibly has a hanging valve that allows a total misfire at times...

 

[Falken]

Next step is to do a Leak Down test, that will identify where the compression is being lost from. You only need to do the test on Cyl#6.

Did they repeat the compression test with a bit of oil dropped down the plug hole to rule out the rings? They should have. Then it would mean a valve is the issue. That is easier to fix than changing the rings.

If the car is in great shape and no Florida salt-air rot, it may be worth getting a scrapper engine dropped into it.

 

[dparm]

Used motors shouldn't be too hard to come by.

 

[BubbaFL]

Left to right, #4, #5, and #6

Does this look like a head gasket that was leaking?

 

[BubbaFL]

Here are the contents of the oil filter.

What are the chances the bottom end survived this?

Worth throwing a couple hundred bucks of gaskets on and see if it knocks, or is that a waste of time and I just start shopping for a new engine?

 

[Falken]

Good news, cheap fix.

A leak down test would have shown bubbles coming out of the rad with the cap off.

Or, if you inspected the plug you'd see burned coolant on it or you'd smell burning cotton candy if it was bad enough, or even seen white smoke at the tailpipe if it was really bad.

Leak down tests are a great diagnostic tool.

Do you have a torque wrench and the bolt tightening sequence? I'd also try and find a head gasket that doesn't need to be re-torqued if possible.

 

[Falken]

Change the gasket and the oil 2x and it will be fine.

I'd use old engine oil if you still have some laying around for the first drain and fill to flush out the coolant in the crank case, then dump, then use PYB.

I doubt it has any engine damage.

 

[supton]

I'd try the head gaskets first. Less work than an engine swap, I'd think, since you've done half the already.

No stretch bolts on the heads?

 

[yonyon]

Originally Posted By: BubbaFL
Left to right, #4, #5, and #6

Does this look like a head gasket that was leaking?



Well let's see: the #6 piston has a clean spot adjacent to a water jacket. Add to that #6 is showing a carboned up valve that two cylinders don't have and could be from an incomplete burn, yeah, it kinda looks like a leaky head gasket.

 

[observer]

i probably check the intake valve on #6 piston lots of carbon deposit.there's a possibility that valve is not sitting properly hence lose compression.

 

[Falken]

If you have a head gasket leak that is where you loose the compression.

As the intake stroke happens, it pulls coolant into the #6 combustion chamber and it basically burns fuel and sugar.

That is why your #6 combustion chamber looks like that. Burnt sugar residue.

For giggles just turn the head over and pour something like rubbing alcohol on the valves and see if it leaks out.

If it doesn't, it is simply a blown head gasket.

 

[BubbaFL]

Thanks for all of the guidance.

That explains the (very slight) rough idle, intermittent misfire, and white smoke at startup that it's had for a month or two.

On further inspection, the front cover, rear main, and oil pan gaskets were all leaking. I decided to pull the engine and replace all of the gaskets, and inspect the bottom end. Bearing pics to follow in a day or two.

Oil choice didn't have anything to do with this failure, but no leaks for a few years on Maxlife... switched to PYB two OCI's ago (December), and now it leaks like a sieve and goes kaboom.

 

[BubbaFL]

The saga of this piece of [censored] continues.

Spent a couple days carefully cleaning the aluminum heads. Finally got all of the gunk off and found this on both heads:



Okay, fine, ordered new heads, started replacing gaskets and seals. Apparently this thing was leaking from every single possible place, even though there was never oil in the driveway.

Put the front cover, water pump, oil pump, and balancer back on.

Lubed up the cylinders, turned the engine over a few times and it didn't feel right, so I flipped it over and took the main bearing caps off.

#1 and #2 (top two) have a HORRID stench and I can feel slight surface roughness on them:




And then I noticed this on the #6 cylinder (the one with low compression):



I'm not very good at this kind of stuff, but I'm pretty sure that thing ain't supposed to be crooked.

Soooooooo, what do you guys suggest? Can I get away with just replacing that one rod and the stinky bearings, or should I just order a reman engine?

 

[tig1]

The only thing I can think of that bent that rod was that #6 hydrauliced from the fluid. I would replace the rod(check the piston for damage) and bearings. If you were close by I would weld repare the heads and have them machined for a song of the price of new heads. I have seen this head problem many times. Coolant gets under the head gasket and pits the alum. Actually an easy fix.

 

[The_Eric]

I guess it depends on where you want to stop. I've done some pretty cheap things in my day to keep running, but I get the impression that it not that critical you get this running again.

A re-man gives you a warranty which is nice. You can just replace that connecting rod and buff the bearings. I wouldn't be too concerned about any perceived roughness as the bearings look to be relatively undamaged. If you absolutely feel you must do something, buy some white Scotch Brite and buff em.

 

[BubbaFL]

Originally Posted By: tig1
The only thing I can think of that bent that rod was that #6 hydrauliced from the fluid. I would replace the rod(check the piston for damage) and bearings. If you were close by I would weld repare the heads and have them machined for a song of the price of new heads. I have seen this head problem many times. Coolant gets under the head gasket and pits the alum. Actually an easy fix.


The new heads (from AAP) only cost about $25 more than having the existing heads machined locally.

Amazing that this thing was actually running without knocking right up until I pulled the engine.

Guess it's time to learn how to rebuild the bottom end now.

 

[ag_ghost]

Sorry to hear of the troubles. Is the motor the 3.0 or the 3.8?
Kevin

 

[BubbaFL]

It's the 3.8

 

[default]

If the bores and journals look ok, I would order a re ring kit for it, add a new rod, and put it back together.