hey everyone,
I have 2 questions:
1st off a little history engine looses rpm at top end (5400-4800) after extended run
fuel bulb pumping does not effect rpm, choke causes engine to bog further. parts that have been replaced stator, power pack, 6 ea coils, regulator, carbs rebuilt. compresssion 84-90psi across the board.
2nd water pressure fell off 2 weeks ago, replaced water pump and housing and still has low pressure 14 at wot 3 at idle(used to 28 and 7)
First off, it will help us a little if you can post your model and serial numbers, as sometimes there are special bullitiens about certain engines...
Second, all the electronics you replaced, was it factory parts or off brand(CDI) PARTS?
As for the water pressure, if it was me , I would take the line loose from the gauge, take it loose from the motor, and blow air thru it to see if i had an obstruction.
model # in post title sn r08605277
electronics are cdi
I think the rest of the mods here are gonna agree with me on this, but probably the power pack is what might be causing your rpm issues...and it might be linked to other parts as well.... i know i personally have not had an issue with there packs, but I know one of the mods can give a testamonial on it and the problems it can cause.... so if it was me, take it to a marina and have the pack tested....
Stop!!! Check compression as a head gasket my be ready to blow. This would allow compression into water jacket causing a false or low reading and 1 cly acting up will drop rpm about 1000rpm.
Bought a set of gray inductive plug wires
from CDI. Would it be a good idea to stop
right there?
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by brad crudup »</TD></TR><TR><TD CLASS="quote">hey everyone,
I have 2 questions:
parts that have been replaced stator, power pack, 6 ea coils, regulator, carbs rebuilt.
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Did you test the timer base assy. while it was acting up?
Start with a compression test then go from there......
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by brad crudup »</TD></TR><TR><TD CLASS="quote">compresssion 84-90psi across the board.
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That compression seems a tad low. I know the V-6 X-flows are usually low but I had an 89 150 gt and it was between 100-105. I'm wondering if you need to have the head gaskets checked like someone else stated. Did you pull all of the plugs out and turn it over with full throttle?
Burning the candle at both ends.
thanks for the replies. I have not been able to check the trigger at wot. In regards to the head gaskets the rpm drop was happening before the water pressure issue but will try to perform a leak down check also. the plug wires are also new not cdi not inductive but solid core. the rpm drop was occurring before the change of the electronics old parts were brp. compression check was done with all plugs removed throttle plates open. timing at wot 28*. Please don't take any answers as arguements I am an aircraft mechanic and have replaced these parts at the advice of local marine tech. A lot of money spent and no results.
Let me start and say, Your motor will NOT live at 28 degrees timing...... In fact I would dare say you might have found your problem.... FLYWHEEL??? It should be 18 degrees total timing, so what I would do is pull #1 up, check it against the timing tab and the marks on the flywheel and go from there.... of corse if the mark is jumping around alot when you are shooting the timing, could be pointing to the bad timer base as well....
You check the flywheel and #1 pulled up?
yes timing pointer and #1 tdc are aligned have not been able to run since posting 40 miles to the lake. just wanted as many ideas as possible when i get to the water. I am getting conflicting info on timing from the dealer and here I'm going to set back to 18* as witchdoctor suggested. leak down check is good 10% all cylinders.
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