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-   -   Another day of great fun... maybe not so much. WTH?! (https://www.offshoreonly.com/forums/general-q/338800-another-day-great-fun-maybe-not-so-much-wth.html)

JRider 07-28-2016 09:42 PM

Not sure how good of a wrench you are, but given your frustration it may be a good idea to take it to a pro and alleviate some headaches through $. I have had a rough go of it myself this year...have a beer, step back and let it go for a while.

TomZ 07-28-2016 10:39 PM

Thanks JRider. I'm my own wrench, and pretty decent at it, if I must say.

I need to re-evaluate some things here, and apply deductive reason. A compression/leak-down test will tell all. I have the equipment to do it so not a big deal.

I need to step back and have that beer, then get into it.

TomZ 07-28-2016 10:45 PM

On a related note... the pops only happen on the intake. The engine ran okay outside of the random pop pop pop that would disable being able to start the engine. I thought that I got rid of that with the new distributor.... she ran well!

I changed the intake gaskets (three times now) and this is what I've got.... a fast-spinning motor on the starter that randomly pops through the intake, then runs and idles fine, but seems lazy. Hitting her hard on the throttle makes her rev; no pop. Timing is set at 30-31 degrees locked.

What am I chasing?

picklenjim 07-28-2016 11:06 PM

Sure you have the cam installed correctly, timing wise.

sutphen 30 07-29-2016 05:46 AM

I'd check that intake valve,,it may be tight in the valve guide.

underpsi68 07-29-2016 06:02 AM

Running lean?

Budman II 07-29-2016 11:31 AM

I had a similar issue with my old 454 years ago - idled fine, albeit a little rich, ran OK at cruising speed, but under load or full throttle would backfire through carb. Compression test revealed one low cylinder. Pulled head and found that I had blown a chunk off the ringland through detonation, and that chunk had hung up in the intake valve and knocked a 1/8" hunk off of it. Hope this is not your issue.

TomZ 07-29-2016 11:38 AM

I'll yank it apart tomorrow... could be a valve adjustment. Either way, an intake valve isn't quite shutting.

More to come!

TomZ 07-30-2016 02:41 PM

Guess I need to rethink my wrenching abilities....

I thought for sure that my firing order was correct. In fact I was so sure about it that even today I didn't go about double checking before tearing into everything. I went through everything on the odd side of the engine (all cylinder tight), then went to the even side. Looked at the wiring (after getting the valve covers off and backing off all the rockers), I found that numbers 2 and 4 were swapped. Dammit!! All cylinders were tight on the even side too. Oh well, at least I was able to test everything.

Trust but verify!! Sometimes it's the littlest of things that mess up the works. In my case, I was rushing to fire it up because I had to be at an after-hours work function.

Now I'm waiting out some thunderstorms so I can put her back together.

Question... I see conflicting information on how to set the preload on Comp lifters. I've always used a 1/4-1/2 a turn from zero lash. The instructions from Comp say 1-full turn, but there are some other instructions state 1/4 and 1/2 and 3/4. The lifters are Comp 854s-16 High Energy roller lifter (retrofit). What's the general concensus?

SB 07-30-2016 02:59 PM

Up to one full turn, where ever you feel most comfortable. I usually go 1/2-3/4 so plenty of margin on either side.

Exhaust just starts to open - adjust intake
Intake just about closed - adjust exhaust


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