motor m issing after 4000rpms (HELP)

[banson1]

I drove my boat two days ago and it was running great. 5000 rpms all night and running good. Today it was running good and half way across the lake it started missing after 4000rpm. I found a pin hole in the water line after it got the aircleaner and intake all wet. I pulled of the distibutor cap aand it was dry.Oh ya after it missed above 4000rpm I would back off the gas aannd it seamed to help for a couple of seconds.
[This message has been edited by banson1 (edited June 09, 2002).]

[Hotcrusader76]

Did you backfire? Are you runnning lean or rich?(Check the spark plugs) What type of carburetor are you useing? Type of motor? Type of igntion? (points, electronic...)
Sounds like you might have an obstruction in the fuel system? Or even a cyclinder going bad...Do a compression check ASAP! Buy a guage for approx $40 at Kragen and plug it in to the spark plug holes...turn the motor over 3 times, and then check the rest. They all should be within 2-3psi of each other. If one is way off, do a leak down check on it.
Give a ring if you need help.
1-619-920-5871
Thanks
Ty Lofstrom
Texas Performance Carburetors
sales@tpcracing.com

[rrrr]

How old are your plug wires? Water + weak insulation = grounded spark.
Simple and cheap to check out.

[banson1]

Its a 355sbc hei distributor with a brand new pertonix coil ans module.Im running a holly 750 vacume seconds

[banson1]

new taylor 8mm in real good shape

[Costello]

Check your fuel filter, pressure regulator, and carb bowls for trash that may be obstructing fuel flow.

[Hotcrusader76]

BANSON1,
I suggest checking the entire fuel system again. I recently had a customer's carburetor come in and it had silicone pieces stuffed in the primary jets. We had no idea where they had come from, but I think there was some sealant coming free from somewhere, and it was up-stream from the filter.
Good Luck bro!
Thanks
Ty Lofstrom
Texas Performance Carburetors
sales@tpcracing.com

[banson1]

I apreciate all of your help. I pulled a valve cover off and found a small piece of the inner spring broken off and laying in the bottom of the head. I am being told that the inner spring is only a dampner and guide I am wondering if its not a valve spring floating??? what do you all think.
Thanks again
Bob

[Hotcrusader76]

I had the same problem on my BBC 468. Busted inner spring. Just replaced them all with a new set. No biggie.....Point is...it's broken, so replace it, then start all over again.
Originally posted by banson1:
I apreciate all of your help. I pulled a valve cover off and found a small piece of the inner spring broken off and laying in the bottom of the head. I am being told that the inner spring is only a dampner and guide I am wondering if its not a valve spring floating??? what do you all think.
Thanks again
Bob