Broken rod at speed, what is next?

[Mad Mike]

I learned today that the issue I had at the last track event was a broken rod. Now pulling big chucks of metal out of the spring plate.

Should I get a second opinion?

Wayne has kindly suggested that he would like to tear down the engine and see what happened. As rods are the hardest part of the engine and should not break on their own. Must of been a rod bolt or some thing else.

Regardless, I am need of a full replacement/rebuild and plan on getting my car back home, pulling the engine, and start the tear down.

Should I sent it to Wayne to make another book out of it?

My mechanic said it was the worst that could of been expected.

And it was a "racing" engine that was fresh 10K mile ago, still in a street car.

PS, I am out of cash and have not other options at this point.

We are considering loading the engine in the car and making a beach trip out of it.

Let me know your thoughts?

Cheers on the day I greneded my engine!

[asphaltgambler]

I would reccomend disassembling your wallet before the engine. Bet on a ruined engine case and crank. No cheap way out here, I've been there.

Best way is find good used stock engine or if you are lucky you may find a fresh or low hour race piece here with documentation.

[Mad Mike]

I am going to start the disassembly in a month or so. Have other obligations the next 3 weekends. And we'll see to what extent the damage is.

It was recommended to me that I start looking for a new case and crank...soon!

Now the dilemma starts, what type of engine do I really want and for only an extra $XXXX, how much faster would it be?

I might disassemble assess the damage, then sit quite until I can afford to do what I want. 3.6.

Will be a good learning experience for me, regardless.

[john walker's workshop]

unfortunately, there's not a lot left to reuse when a rod goes at speed. case, oil pump, crank, pistons, cylinders all get damaged in some way.

[TimT]

not for the faint of heart

[Mad Mike]

TimT,

Did a broken rod lead to your broken crank?

[Wayne 962]

Hi Mike. I spoke with a few people today, and mentioned your engine to them. Consensus is that 3.0 rods do not break - they are broken by something else. We won't know until we open up the engine. There could be many salvageable parts in there, but we won't know until we get it on the stand and tear it down. Even if you were to sell it as a "core" on eBay, you wouldn't get more than a couple of bucks for it, because all the parts inside are in question - it needs to be opened up to find out what went wrong, and also what is salvageable for your next engine and/or to be sold.

That said, there are a few things that are very suspect:

- This is a new rebuild, which means that there is a chance that there was a "builder error" in assembly. A piston installed upside down will function find until an overrev, and then slowly disintegrate.

- Rod bolts falling off, if they were not tightened properly will do the same.

- Dropped valve seat. Not very common on these cars, but very common on VW type IV engines. If you look in our tech articles, you can see a Type IV that had a rod do through the case due to a dropped valve seat.

- Along the same lines, it's possible that something fell into the combustion chamber. Basically, the rods don't break - they are broken in the process of something else failing. Your engine didn't stop because of a broken rod - the rod was broken by something else that then made your engine stop.

Bring it on by next month, and we'll take a look at it.

-Wayne

[Mad Mike]

Thanks Wayne for the offer,

I am curious to see what the cause was for the rod breaking. After our conversation last night, got me thinking the engine may of been incorrectly built. Don't know, it was not my car 10,000 miles ago.

Will let you know what the steps taken in preparation of the trip.

Hope it can fit in a Pacifica! We are going to make a beach trip out of it for the wife and boy. All staying with my brother Scott.

Regardless, we (I) will get to the root of the problem and go from there. I have a feeling this might be a long project to get the car running again. I will be saving for a 3.6 liter, preferably a 1995 993 engine.

Thanks again Wayne for your advise last night!

Mike

[Eagledriver]

I see in your post that your car has a 3.2. Is this a car with a Carrera engine or a SC engine with 98mm cylinders? If you have the longer stroke 3.2 then you may have had a rod bolt fail. These are more failure prone than the earlier rod bolts. The long stroke engine should have ARP or equivalent, especially in a race engine.

-Andy

[Mad Mike]

It WAS a short stroke, 3.0 case with 98MM jugs. 9.3:1 Pistons 21/20 web cams...

Really, I am looking forward to detecting the issue. So many things are wrong with this that I can't even start.

End result will be Pelicanized!

[mb911]

wow what a terrible thing to happen but at the same time what a great offer from wayne to help you out. I am very impressed. Keep us up to date

[Henry Schmidt]

About four years ago, I had the occasion to disassemble a 3.5 turbo engine from a PCA race car.
The car was racing when it suddenly started to smoke.
The car was driven into the pits and parked.
At that time I had the pleasure of trying to ascertain the problem.
The smoking was caused by a magic window in the top of the case.
Upon inspection we discovered that the connecting rod had broken in the middle about 1 1/2 inches from the small end.
The rod bolts were in tact and the crank was inspected for cracks and straightness then reused.
The piston was entirely in tact. No valve was even bent.
There was damage to the case and the base of the cylinder.
The rod was sent to Critical Operations for analyses and the conclusion was a crack from a stress riser as the result of a casting flaw.
One thing you'll know if you do enough engines is that you haven't seen it all. Now, when we build race engines with used rods is that magna flux for cracks is required.
This flaw in a normally aspirated engine or even a turbo used on the street may have lasted the life of the engine.

[Mr9146]

Bummer. I'm sorry for your loss.

Good luck with your replacement.