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Loss of power at higher speed

"On my second Crusader 220 eng

"On my second Crusader 220 engine I have experienced sudden loss of power at about 3000 rpm, at about 11 knots speed. I noticed earlier that my oil pressure gauge was reading at neutral 25 psi, while the other engine was showing 55 psi. I changed the gauge and also replaced the sender, but no difference was noticed. Then we had a short ride out and that's when we experienced sudden drop of rpm and loss of power. A friend is telling me that I should check the compression which may be a cause of this problem. He said I may have worn out rings or busted head gasket? What compression reading should I get from a normal engine? This is a small Chevy 305 V-8.
Thanks for your reply.
Gene"
 
Question(s):

1. Did


Question(s):

1. Did you "cure" the low oil pressure problem?

2. Do you have an electric fuel pump?

Jeff
 
"[b]"What compression read

""What compression reading should I get from a normal engine? This is a small Chevy 305 V-8."

Ayuh,...

It's the Spread between the #s, rather than the actual #s that count....

You shouldn't see more than 10%/ 15% difference between the Highest #,+ the Lowest #...."
 
Lack of fuel pressure to the c

Lack of fuel pressure to the carb. Failure of the carb secondary. Failure to advance the distributor. Plugged on-carb fuel filter come to mind.
 
"Fastjeff: I didn't cure t

"Fastjeff: I didn't cure the low pressure problem. My fuel pump is mechanical.
Bondo: I took the compression readings on the 4 left side cylinders (most accessible). The readings were ranging from 125 to 150, not bad according to my manual which states that anything below 105 will indicate problems.
Diver dave: Your comments are very logical and I will recheck the fuel pressure. Carb was rebuilt but how can I check secondary after re-installing. Engine runs at idle normally and it gets to desired speed easily, but when running steady at 3200 rpm it dropped the rpm to 1500 suddenly, and then, after a few seconds it got up to the 3200 rpm. It happened four or five times within a 30 min ride. I will also check the fuel filter on carb and replace it with new.
Thanks guys!"
 
"25psi at idle is in spec, and

"25psi at idle is in spec, and in itself, is nothing to worry about. One engine may have tighter bearing clearances and/or oil pump clearances causing higher idle pressure. The engine doesn't need higher pressure than 25 below 2000 rpm. Does this change with a new oil filter?
If this engine suddenly looses power at speed and runs rough, I'd think ignition, but if it looses power and runs smooth, I'd think gas flow; but, those are major generalizations. You may be able to view fuel in the secondaries of the carb at speed, but there are some safety risks associated with that experiment."
 
"how old is the fuel pump?

"how old is the fuel pump?

last time the fuel filter(s) were changed?

All of the fuel line, tank to carb, inspected for cracks, loose hose clamps, etc?"
 
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