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popping at speed?


popping at speed?

Old 07-26-2002, 08:18 PM
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Just look for the 272 SR1 in the driveway along side the house.White with black,teal,and magenta stripes. Missed the "Scarab", I don't get over in that direction too often. Traffic on 322 can be a pain in the @$$
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Old 07-27-2002, 11:53 AM
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I'm thinking that hose isn't the problem, then again... I'm more inline with Mopower's suggestion of valve related problems especially since you said it does the popping at steady throttle. Timing and carb usually go with accelleration. Popping anytime often comes from burnt or bent valves OR broken/weak valve springs which are easy to check and replace.

Note the threads on Merc HP-500 carb motor's valve springs. Very similar and I've personally changed some in a friend's HP that wasn't revving right/popping. Make sure your springs match your cam requirements. What did the shop that rebuilt them put in?

Keep us informed with your findings.

Old 07-28-2002, 12:20 AM
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Try unhooking that vent line going to the intake first. The suction on the back of your (fuel pump) diaphram is a problem. It should go to the air cleaner.
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Old 07-28-2002, 07:10 PM
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Do you have ignition points?

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Old 07-28-2002, 11:54 PM
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I say cam lobe. Mine did the same thing. It will get worse and then you will know. Check for milky oil. Mine leaked at the riser and washed the cam with water/oil, Took the lobe right off.
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Old 07-30-2002, 03:18 AM
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I never thought of checking the valve springs...

the springs work with the cam I have.....

I didint get a chance to play with the vent line this weekend...

Ive had my eyes on a set of gt-4o cast iron heads for it that go for 500+ I luv ford racings stuff.....

are there any heads that are better then the CAST IRON gt-40 heads? and for a nice price around, 500+?

I have a extra set of ford heads that I could get worked on but I would only work them if it was economically viable, you know bang for my buck kinda thing....

the ignition is all electronic(MSD 6t with rev control box) with a msd distributor/mechanical advance...
and a accel coil.

I'm hoping its the fuel overflow hose.....
and a bit of a timing issue....

I know its not suppose to pop if i hit the gas abruptly and ive been told its a sign of to much retard... hehe I think im just being retarded.....

had a nice weekend......
went out in 4-6 foot rollling swells......

I get my 24pitch prop this week....

Cant wait to try a nice new prop .....

my aluminum prop is so freakin shot out.......
gouges and one of my blades is bent from heating the blade up ....to much from cavitation....

I should be in 55+ range hopefully close to 60 MPh then ill get the pitch turned up to 25 or 26 ....... woohoooo
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Old 10-31-2013, 11:08 PM
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Ever find the issue?
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Old 11-01-2013, 06:44 PM
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Fuel pump vent hose should go ABOVE the throttle plates into the carb. That way, if you rupture a diaphragm, the gasoline goes into the motor - not into the bilge. But you cannot run that hose to a vacuum source or it will suck the diaphragms closed on the pump. If you have a marine carb, then you have the correct fitting on the carb to connect the hose to. If you do not, you can run a piece of hard brake line into your flame arrestor and have it aimed into the carb primary throat and hook the hose to that.

You can easily check to see if you are collapsing the pump diaphragms by disconnecting the hose from the intake - plugging the intake source that you were using, and running the boat with the hose not hooked to anything for a few minutes to see if that fixes it.

If that doesn't fix it, check your water separators for water (fuel filters..).

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