Tank was topped off before winterizing back in Oct. I keep the tank like 3/4-7/8 full over the winter.
It looks like I didn't mention in the original post, that I did my un-winterizing check ride the week before all this on the topped off tank and I was out for several hours with no issues...
If this helps.....the backfiring only occurred a couple times. When I was accelerating, I heard the "pop" noise from under the so called hood/back seat. I backed off to idle, then tried accelerating again, heard another pop....so maybe 3-4 pops total over the whole course of trying accelerate...
Compression test on a cold engine. Thought this would be the better test without any heat expansion involved. I believe this shows no leaky valves.
#1 158
#3 160
#5 160
#7 170
#2 165
#4 153
#6 147
#8 160
The spark plugs look good. Do I shift my focus over to a fuel issue?
Not to go down another path here.....I'm still going to do the compression testing..... Did some additional reading and talking to some other folks and they're pointing me to a fuel issue, specifically a lean fuel condition.
Since everything ran fine 2 day prior and the fact that I topped off...
Any recommendations for an engine compression test kit. I see a couple at harbor freight but I understand I need to find a kit that has the correct size fitting for the spark plug hole.
Monday was kind of a freaky day if you're a superstitious person. After dropping the boat in the water and went to start it, the fuel gauge wasn't working...it was working on Friday. I disconnected/re-connected the connector at the tank and then all was fine. While in the channel heading out...
The update.....
Put new cap and rotor on....old ones didn't really look bad.....either way, problem still exists.
Starting with a cold engine, it died twice but finally stayed running but sounded rough with an irregular rpm. As it warmed up a little bit, started to sound better even though...
Just an off the cuff question.....in the case of my engine with a distributor, how does the ECM advance or retard timing when you have a fixed rotor rotating around making contact with the "points" on the dist cap? I'd think you couldn't advance or retard too much otherwise the rotor won't be...
It's not surging at idle, only when I add a little throttle. Otherwise the engine sounds/feels normal when at idle.
Last year when I addressed my fuel pressure issue, I replaced all the vacuum lines. My vac readings came from inserting the vac gauge right at the port on the intake manifold...
My bad on the vac readings...... those numbers I posted were in cmHg.
To revise them....
At idle around 12 inHg.
When surging, 7 to 12.5 in Hg.
That is one thing I didn't check yet when I got home last night. But cap, rotor, wires were replaced in 2023, plugs replaced last season after...
The engine was experiencing some backfiring through the throttle body when trying to accelerate and at times sounded like it wanted to stall out at idle. I replaced the tstat on Friday and fired it up, got it up to temp, cracked the throttle a little bit...maybe 800-1000 rpms for a few seconds...
I've been digging around the forum to what info there is regarding how long manifolds last in non-fresh water environments.
I've got a 2005 Chap 256SSi with the MX 6.2 MPI s/n 0W061713, Bravo 3. I've owned the boat going on 6 years and bought it with 160 some hrs on it. It was a fresh water...
Is there is an equivalent slip on rotor to the Kodiac Dacromat 10in/5 lug slip on rotor for 3500# axles?. On Kodiac's site, they are selling for $105 a pop.
https://www.kodiaktrailerbrakes.com/Kodiak-Trailer-Disc-Brake-5-Lug-10-inch-Slip-on-Replacement-Rotor_p_753.html
