okay I just put my new motors in the boat last week 1st one was a pita to start found out spark plug wiring was wrong finally got it to run for about 15 min then it just quit. couldnt get it to restart starter was making a weird noiselike it was under a big load. engine builder said the motor was in vapor lock so went to 2nd motor fired right up ran for about 30 min. and all was fine then tried to restart and same noise coming out of the starter. wtf? checked the lifters on the first motor #1 cylinder intake had a bad lifter pulled the intake and fouind the bottem half of the lifter gone and just the spring setting on the cam it also bent the push rod. pulled the second intake and everything looks ok... i hope.

question is what causes vapor llock and could it be why the motor is turning over hard?
second what would cause a lifter to come apart? bad partsor builder error? he said everything was set to spec. parts were all from comp cams should I wait for there in put or just be new parts and start over?

That was not vapor lock! Time to find a new mechanic. Was it a roller cam or flat tappet?

the cam was hydrolic flat tappet im kinda leaning on a coil bind maybe he tightened the lifters to tight?

I wiped out 2 comp cams cams (flat hyd) this spring in my port engine. Lifters measured soft by 10pts rockwell c on the crown of the lifter. Third cam I got had a different lifter design and broke in ok. Both cams went during breakin. SB engine broke in fine. Only thing I did different on the 3rd cam was remove the inner valve springs for breaking. What a Pita!! Never had to do that before, but that was what comp cams said was wrong. I think with 120psi seat pressure they are full of chit. I sent the cams back and hope to at least get a refund on them. I had to eat the cost of rebuilding the brand new engine with only 30 minutes run time on the shop floor. If you wiped both cams I would look for a different cam brand.

BT

My guess is that the lifters were not adjusted correctly, to tight, and you took a lobe off. I would venture to guess the rest are badly worn.

If so you need to remove the engine and pull the pan and check the bearings. Cast iron material can be very hard on bearings.

Flat tappet cam warning. We lost 2 lifter mfg about 3 years ago. Since then warranties on cams have gone through the roof. To compound this the Gov. made the oil companies remove some anti wear additives from oil since all or most OEM cars now have roller type valve train. This to has led to a high rate of camshaft failures. I highly recommend roller hyds when retro fitting. The upfront cost is higher but if a flat tappet fails you will spend 3 fold for what the retro roller cost would be.

If you just have to use a flat:
Use GM EOS during breakin.
Ask for cam to be ground on a 55 Core. Harder then stock.
Overfill the crank case for breakin only. This will allow additional oil to be splashed on the cam during break in.
Cross fingers.


Chris

On top of what Chris said, for flat tappet cam

And dont crank it forever if it wont start, dont idle it at all. Put a know good carb and distributor on it and time it static (if you dont know how I can help). Start it right away and take it to 2000rpm, no less than 1500. Vary between 2000-2500 for a 1/2 hr.