"Popping" sound, Pop Pop Pop

[noahsinclair]

After fixing (I hope) one problem, I went to test out in water and when I started at launch dock I hear a loud Pop. I'm thinking a distributor issue? I took out each plug (8) and put back in thinking maybe got loose? Still hearing sound, pop vroom vroom pop etc. I cancelled trip, put back on trailer, started when out of water (no more than 5 seconds) and she started right back up no popping or knocking sound? Hmm... I'd like to use boat I just got, any help would be greatly appreciated

 

[PatinIdaho]

What boat? What engine? What year?
We all assume a Detroit 8V62 and you removed the glow plugs unless you tell us otherwise

 

[noahsinclair]

Sorry I'm a rookie... Skipjack 20 open.. 2003 rebuilt Volvo penta 305 I/O with Volvo Outdrive. V8. Yes I believe they are called glow plugs? It's the octopus looking thing

 

[jimmbo]

Glow plugs are in diesels. A 305 is a gas engine. If you are referring to the distributor as 'the octopus looking thing' perhaps you should not be tinkering with something that has the potential to blow up your boat

 

[noahsinclair]

Sorry wasn't sure what you were referring to, yes gasoline engine. By "tinkering" all I did was while the boat and batteries are off, took out each plug one at a time and put back in thinking maybe one got loose.

 

[bnicov]

Take the distributor cap off and check the contacts inside. If they are all corroded and gnarly looking, replace the cap and the rotor. Make sure you put the pkug wires in the right place. Take your time doing this. It is an ignition or fuel problem. The ignition side is really easy. Fuel problems are tougher to deal with, not impossible, just much more involved. I had a similar issue, new cap and rotor fixed it. Enjoy your boat.

 

[noahsinclair]

Take the distributor cap off and check the contacts inside. If they are all corroded and gnarly looking, replace the cap and the rotor. Make sure you put the pkug wires in the right place. Take your time doing this. It is an ignition or fuel problem. The ignition side is really easy. Fuel problems are tougher to deal with, not impossible, just much more involved. I had a similar issue, new cap and rotor fixed it. Enjoy your boat.

Cap is new, plugs are good, no moisture etc. Its 'popping through the carb', I know a carb can't backfire. Im thinking a lifter, or timing is off or something like that . Im bucking up and going to pay a mechanic. I will repost once I know the diagnosis for future reference.

 

[BellevilleMXZ]

I'll bet you have tore up a lifter/cam lobe with all that water in there over time......was a lot of rust inside that engine pic you posted.

 

[noahsinclair]

Diagnosis....as per mechanic who tested it. I was told I need a valve job, he quoted me $3500-$4000. That seams a bit high to me but Im not sure, anyone know if thats about right? He also said I needed work on my exhaust and quoted me another $2000.

 

[BigJoeB]

Hello,

I have similar issues and just made a post to hear some feedback. I had done the heads a few years ago, actually let marina do it and it was 3500. I didnt want to take of work and lose the day or 2 pay, meanwhile I could have done it for about 1000. including everthing .