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Another Engine rebuilt

It looks like you can add me to the list of people that need a new engine:(

I was at VIR last weekend and by the last session of the first day my catch can (Peterson) was puking oil all over the engine bay. In the 5 years that I had this mod I only had to remove about a shot glass from it during yearly maintenance, so it was quite a surprise to see it puke oil everywhere.

Cleaned every thing and emptied the can and tried to gave it a go on the second day by limiting my run time to 10-15min. Results were pretty bad. Can is full, about 0.6 quart and oil dripping on hot headers. Also the engine consumed about 1-1,5 quart in that time frame. Was full when I started, was below the bottom hole when I pulled in.

Tried again once more and another 1 time at Watkins Glen couple days later with the same results.

Got home and pulled the plugs, brand new with only 1 day at the track, and did a compression test. Tried to do a leak down test but the cheap Harbor Freight broke down on the first cylinder.
Here's the result :
Cyl 1 : 0.051" gap and 115PSI comp
Cyl 2 : less than 0.020" and 120PSI
Cyl 3 : 0.045" and 120PSI
Cyl 4 : 0.049" and 130PSI
Cyl 5 : 0.034" and 125PSI
Cyl 6 : 0.056" and 130PSI
Cyl 7 : 0.051" and 110PSI
Cyl 8 : 0.050" and 135PSI

All plugs were between 0.050" and 0.052" when installed
Compression tes was done DRY with all plugs removed, Fuel pump fuse removed, flood starting method(accelerator to the floor) and 2 starting cycles.

Here's a video of how much air is escaping from the valve cover at idle. It does pick up the pace if I blip the throttle. Also can plug them with my finger and can feel the pressure rise up.
 

Mad Hatter

Gotta go Faster
4,674
3,393
Santiago, Chile
How many track hours did you have?,,, I imagine it must be over 200 hrs?? Your compression is a little better then mine was ... With luck it will be all std inside with no major dramas... all I needed was rings...(plus all the ARP goodies and normal wear stuff).... Good time for the AED cams!!
 
4,824
5,563
sounds odd that the engine would just start puking oil all by itself, did it overheat or overrev?. We've brutalized these engines without much issue
 
Bummer but you are not alone. Remember: we can build it Better, Stronger, Faster. Good luck with the rebuild.
 
Car has ~22000mi and about 10000 of them are on a racetrack.
Basic maintenances (plug and oil) and mostly stock (headers, intake, tune and oil pan)
I have been running at 8000rpm and have been past up to the rev limiter at 8200rpm more than I would like to admit.
Also only running 93pump gas.

Unfortunate and really sorry to hear. You are going through my EXACT issues I had at my last track event at VIR.
Sent from my iPhone using Tapatalk

Did you find out what went wrong?
I'm thinking bad rings.

I'll rebuilt better and stronger.
 
203
323
Exp. Type
HPDE
Exp. Level
3-5 Years
Scottsdale, AZ
Did you find out what went wrong?
I'm thinking bad rings.

I'll rebuilt better and stronger.

Pistons looked fine but rings lost tension in cylinders 7 and 8. Wasn’t catastrophic (car still ran VERY strong, 151 mph on back straight at VIR) but filling the breather on every run and puking oil out onto the exhaust manifolds was a fire ball waiting to happen. Good luck, let me know if i can be of any help.


Sent from my iPhone using Tapatalk
 
I have been running at 8000rpm and have been past up to the rev limiter at 8200rpm more than I would like to admit.
It seems your Trakwack ways Finally caught up with you. Rev limiters are there a reason, not a suggestion. Track boys seem to laugh at that until they experience what you have.My Boss has never seen a track but I can understand the adrenaline that happens when you're wide open and coming up on a sharp turn!Good luck getting your bad boy back where it belongs!!!!!!!!!!
 
242
124
If I had to guess you have a cracked piston from detention But I think its possible that it might be ok as well.

I had a weird issue before where my vacuum system was actually causing oil to pool in the head and then puke the catch can.

Can you get a video of the blow by while revving the car? When on track does the car fill with oil smoke instantly or just take a couple of laps?
 

Mad Hatter

Gotta go Faster
4,674
3,393
Santiago, Chile
@Mad Hatter and @gtorpedo - I don't recall either of you losing the plug gaps. Is that right?

I wouldn't fire it up any more...and get a borescope in there or start the tear down. Good luck and I hope it's not bad.

No, no problem with the plug gaps. just lower compression and failed leak down test (+10%). The sooner you see inside the better.. I was very happy with my engine builder, they had the engine rebuilt and in the car for less then importing a Ford short block
 

Mad Hatter

Gotta go Faster
4,674
3,393
Santiago, Chile
Oh, what oil are you using??? We had a dodgy lot of Royal purple oil here in Chile that would do exactly the same symptoms.... My buddy changed to Redline at the track and problem went away the next time out.... Might have been a counterfeit oil or some such...

But in your case you are already with lower compression
 
If I had to guess you have a cracked piston from detention But I think its possible that it might be ok as well.

I had a weird issue before where my vacuum system was actually causing oil to pool in the head and then puke the catch can.

Can you get a video of the blow by while revving the car? When on track does the car fill with oil smoke instantly or just take a couple of laps?

It would smoke from the can as soon as starting the engine but it will take a couple laps to fill it up and then start puking oil.

I've been using Amsoil pretty much from day 1
I also got a boroscope today and nothing obvious was wrong.

I'm waiting for my friend input then will take it from here but I'm 99% sure that the engine will have to come apart.
 
Drained the oil today and this is what I found on the magnetic drain plug along with metal dust.
Looks like parts of the oil ring.

I should have the engine out by next weekend and will remove the pan to see what's going on

48276545226_8fc5c062d2_h.jpg
48276544226_2902f8edea_h.jpg
 

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