Severity of Broken Valve Damage

[N404CX]

I was inspired to post this message by Brady Lane's latest article where he asks veterans for help.

My brand new 2180 with less than 30 minutes on it had an intake valve break. It ruined the head, the intake manifold, and chewed up the top of the piston pretty well.

1967

Can I replace the broken/damaged parts and trust there is no internal damage, or should I insist the builder open up the case.

Thanks.

[Neil]

The safe answer is to say tear it down and see if there is any damage to the rod such as being bent since it appears that the piston was impacted right over the wrist pin boss on one side. You may be able to remove the rod from the crank shaft by removing the opposite cylinder and uppon evaluating what you see, have a talk with the builder and get his opinion.

Usually when a valve breaks so early in the life of an engine it is a faulty valve. Many valves are made in two pieces, those being the stem and the head. I flew most of the hours in my log book behind a VW conversion without a valve failure and I used the one piece stainless valves from Manley Valve Company. That is not to say I never had any issues. I had problems with valve guides due to a flawed head casting. Also there were valve spring issues that were solved by converting to Chevrolet valve springs but that is another story.

I am curious, did the valve simply break, or did it stick in the guide and was then broken when the piston hit the valve?

[N404CX]

I am curious, did the valve simply break, or did it stick in the guide and was then broken when the piston hit the valve?

It did not stick in the guide. It is broken right below the keeper, and again mid-shaft. The part with the head is pounded into the cylinder head, and the piece of the shaft is jammed into the intake chamber.

1968

[Neil]

Among the things I think you should consider is to replace all the intake valves as the odds are they are all from the same lot.

[steveinindy]

Among the things I think you should consider is to replace all the intake valves as the odds are they are all from the same lot.

That would be my suggestion but then again I'm not an "engine guy". I'm just glad to hear that you're OK and are able to be around to worry about this.

All the best,

Steve

[WLIU]

Question,

If broken bits went into the intake manifold, did some get sucked into other cylinders? That happens with other engines that have failures of the type described. Other cylinders can suffer FOD damage.

Does an examination of the oil screen or cutting open the oil filter show any debris from the failure? You will likely need to flush the entire engine to get any debris cleaned out.

Best of luck,

Wes
N78PS

[N404CX]

Thanks, Wes, I think anything in the adjacent cyl. can be cleaned out.

[CraigCantwell]

Looking at the pictures, were it my engine, there would be no question about opening up the case. You had enough force on the piston to drive that valve into the head. Without pulling it apart, you have no way of knowing if there was damage to the rod and the crank. I would be looking particularly at the rod, crank and the case around the cylinder studs. I hope that you don't find any damage, but it would be much better to find it now than on takeoff.

[Bill Greenwood]

What is a "2180" , never heard of one?

[N404CX]

VW engine of 2180 cc. displacement, horiz. opposed 4-cyl. 92mm bore, 82mm stroke.

[douglish]

You are asking the wrong questions.

With thirty minutes on the motor, I would chuck the lot in a box and drive back to the builder. Take a tent and camp on his lawn until he puts a NEW MOTOR in your pickup. What he does with the old parts is not your affair.

DO NOT, DO NOT, get involved in discussions about valves, pistons, spark plugs, politics or religion.

If you are a little guy a pick handle would be handy too.

[Neil]

Douglish, you have a valid point. The engine builder, if that is his profession, has a responsibility here. Either refund, replace or rebuild. I've always built or rebuilt my own engines so any problems I ever had were my own. I think we all were just answering the original question here.

[spungey]

It's been another week ... what did you decide to do?

[N404CX]

The engine builder replaced both heads, rocker arm assemblies, and the damaged piston. Am installing now.