Re: frustrated
you are describing a fuel issue.
when was the last time the fuel pumps were rebuilt or replaced?
as far as the carbs go its very simple. if you dont tear the carb to intake gasket they can normally be reused,always replace the fuel bowl gaskets.
if the needle valves are not leaking then all I would change is the orings on the high speed jets,if applicable and the bowl gaskets.
its old enough that without pictures of the carbs or the powerhead its hard for me to get more specific out of memory.
but lets do a bit of testing.
test compression
test spark,it must be able to jump a 7/16th gap.
after that the average back yard guy is stuck with fuel.
at the shop the next step would be a fuel system vacum test.
we have a pump with a vacum guage and a flow meter set up, what your looking for is less than 4"Hg at WOT which is roughly 16GPH for your engine.
if that passed it would be on to test wheel YB1626 and a session with a peak reading multimeter if electrical problems were suspect.
you can monitor ign coil primary and secondary voltages with the correct test equipment, also pulser coil voltages can be monitored.
I dont like resistance tests much as I would rather see the loaded working voltage outputs.
if the oil control module has been replaced recently it will have black resistor plug caps but originally the Pro V 150 motors from 84-93 had standard plug caps.
the electronics are rather bullit proof and very easy to test.
you can buy an analog peak reading meter anyplace that sell sierra products for about 90 dollars just be aware unlike digital stuff it is polarity sensitive.
its how I ended up with 2 stevens CD-77 1 seriia merc 2 flukes and a couple of radio shack meters.
just depends on what I need to check and where.
flukes we dont take on the water,they dont swim well at all.
OTC,snap-on and a few others make a Kv tester to test the ign coil secondary voltage.
thats why I say after the fuel system tests and a good carb cleaning the back yard guy simply doesnt usually have the test equipment or training to use it to justify the cost of buying it,come to think of it I know a lot of techs the same way.
so lets start with the basics,vacum guage is about 20 dollars and you will need a few T fittings. T into the system between the engine filter and the lower fuel pump intake,at WOT you should see between 1 and 3"Hg, less usually indicates an air leak more indicates a fuel restriction.
carbs on that engine are very simple do clean as the pilot fuel jet and themain jets are located in the fuel bowls.
remove and dissasemble the bowls,soak just the bowls and jets,spray the carb body out DO NOT soak the carb bodys.
reassemble with new bowl gaskets and main jets orings as applicable. no need for full kits normally unless the needles are leaking which causes flooding at low speeds and doesnt fit your description.
