Engine issues

[Don S]

Re: Engine issues

Does your engine have a Mercruiser Serial number?

Did you do any of the tests in the link I posted back at the beginning of this thread?

 

[Mac525]

Re: Engine issues

Man I cant believe how many of us have this very same problem merc really needs to recall these distributors and fix this once and for all try regapping the plugs to .035 from the .060 that is in the specs to prevent spark jump in the cap if this fixes your issue you can go to .040 and retry but most of us are staying with .035

PS you may have gotten a bad new cap this is also very common volvo makes one with brass conectors which is alot better

 

[Don S]

Re: Engine issues

Man I cant believe how many of us have this very same problem merc really needs to recall these distributors and fix this once and for all try regapping the plugs to .035 from the .060 that is in the specs to prevent spark jump in the cap if this fixes your issue you can go to .040 and retry but most of us are staying with .035

PS you may have gotten a bad new cap this is also very common volvo makes one with brass conectors which is alot better

How can you blame it on Merc and the distributor when you don't even know which distributor he has? or even if the distributor is the problem. And you don't go regapping plugs for the fun of it either.
If that's not bad enough, Volvo doesn't make a cap for Thunderbolt ignitions if that is what he has.
It's probably a fuel problem anyway, not a distributor problem, so why would Merc recall the distributors ???????

 

[tedhrs]

Re: Engine issues

Okay got it started this morning. Spray some gas in the Carb and it fired right off...ran for a second shut off. Did this procedure again, gave half throttle and it stayed running.....ran great. I let it run for a little bit and then shut it off. I did this several times and every time it would start great and run great....problem solved.....no.

Took it to the water, idled out past no wake zone, slowly eased in to the throttle and pop pop run...got up on plane and ran on up to 4000 rpms just fine....doesn't go past that....looked at my guages and everything looked normal...oil pressure above 60, temp at 150, voltage right around 12.5....
So I'm like okay....it was cleaning itself hence the popping....wrong...made a couple turns then lost Rpms, started popping a lot and then shut off. Couldn't get it started again....felt risers for heat and omg I couldn't put my hand on em. I anchored and sat and let it cool down.....got it started finally and the temp guage was at like 180 and the alarm was going off...I watched the Guage go down and the alarm go off as it hit the 160 mark.....got it going and up on plane and it popped the whole time....couldn't get about e 3500 rpms.

I'm stumped at this point.

 

[Mac525]

Re: Engine issues

OK Don I've made a few assumptions here as you have in many posts before... and this is a very common problem with the crab style cap and rotor regapping the plugs "for fun as you say" is and easy way to fix this cross fire problem. If this is the "crab cap" volvo uses a msd one that they sell which has brass conductors. Do a google search for 350 mpi mag back fire and or loss of power, and you can have fun reading for days about how this problem has affected people and how it is almost always looked at as a fuel problem..... Tedhrs take all advice for what it is there are a number of things that could make this happen any resistance between the cap and the plug can cause spark jump and misfire bad wire, bad cap, bad plug, to much gap.

Don just because you dont agree with my opinion or are not aware of a certain problem doesn't mean your right. I didnt tell him what I thought to waste his time or mine, clearly you have a vested interest in merc and I'm not "bashing" them or you, I own one too, if this is not what the forum is for than maybe I'm mistaken

 

[Don S]

Re: Engine issues

Okay got it started this morning. Spray some gas in the Carb and it fired right off...ran for a second shut off. Did this procedure again, gave half throttle and it stayed running.....ran great. I let it run for a little bit and then shut it off. I did this several times and every time it would start great and run great....problem solved.....no.

Took it to the water, idled out past no wake zone, slowly eased in to the throttle and pop pop run...got up on plane and ran on up to 4000 rpms just fine....doesn't go past that....looked at my guages and everything looked normal...oil pressure above 60, temp at 150, voltage right around 12.5....
So I'm like okay....it was cleaning itself hence the popping....wrong...made a couple turns then lost Rpms, started popping a lot and then shut off. Couldn't get it started again....felt risers for heat and omg I couldn't put my hand on em. I anchored and sat and let it cool down.....got it started finally and the temp guage was at like 180 and the alarm was going off...I watched the Guage go down and the alarm go off as it hit the 160 mark.....got it going and up on plane and it popped the whole time....couldn't get about e 3500 rpms.

I'm stumped at this point.

Well, it appears ted isn't going to tell us what he has. So I guess we will all be stumped.

 

[tedhrs]

Re: Engine issues

Man I cant believe how many of us have this very same problem merc really needs to recall these distributors and fix this once and for all try regapping the plugs to .035 from the .060 that is in the specs to prevent spark jump in the cap if this fixes your issue you can go to .040 and retry but most of us are staying with .035

PS you may have gotten a bad new cap this is also very common volvo makes one with brass conectors which is alot better

all of the plugs are gapped at .040. I can take em all out and redo it to .035 but that doesn't explain the heat up issue...
if there is a blockage in the exhaust somewhere, would that cause the popping and overheating?

 

[tedhrs]

Re: Engine issues

Well, it appears ted isn't going to tell us what he has. So I guess we will all be stumped.

What exactly are you wanting to know?

 

[Don S]

Re: Engine issues

From reply #21

Does your engine have a Mercruiser Serial number?

Did you do any of the tests in the link I posted back at the beginning of this thread?

At this point, we don't know if you have a 1986 350 Magnum, or a 2011 350 Magnum, and they aren't even close to being the same.

 

[tedhrs]

Re: Engine issues

i am sure it does have a serial number, i'll have to go get it although i'm not sure how that is going to help. And yes i did try some of those things. I tested voltage across the coil, i tested spark.

is there a way to tell of the exhaust is blocked?

 

[tedhrs]

Re: Engine issues

From reply #21



At this point, we don't know if you have a 1986 350 Magnum, or a 2011 350 Magnum, and they aren't even close to being the same.

Well, it is a 1988 boat so i assume it has a 1988 or 1989 350 magnum in it. but i'll get serial and verify for you.

 

[Mac525]

Re: Engine issues

yes a blockage could cause those symptoms and don is looking for sn of the motor. I don't think a .005 change in gap will help and the cap issue do not usually have a over heat symptom caused by it. You may have gotten a bad cap new do you still have the old one

 

[tedhrs]

Re: Engine issues

Well, it is a 1988 boat so i assume it has a 1988 or 1989 350 magnum in it. but i'll get serial and verify for you.

There is a little tag that says 350 magazine 1347-8289

 

[tedhrs]

Re: Engine issues

Ob988004

 

[tedhrs]

Re: Engine issues

bump

 

[tedhrs]

Re: Engine issues

yes a blockage could cause those symptoms and don is looking for sn of the motor. I don't think a .005 change in gap will help and the cap issue do not usually have a over heat symptom caused by it. You may have gotten a bad cap new do you still have the old one

I have put the old cap and rotor back on to see if it makes a difference. Will take her out today. After bringing it home on saturday and running it on the muffs, it ran perfect again.

I think at this point i'm going to take it to get it looked at since it doesn't seem to be a firing issue. It may be a fuel issue but i am not going to tear my system apart to check, i'll pay someone to do that.
It could turn out to be an exhaust blockage in which i tried to take the rubber pieces off the riser to look down inside, but i couldn't get enough flex on the rubber to pull it off. I have noticed that since i've the boat that the starboard side manifold has always been warmer than the port side. I can still put my hand on it and hold it there, so i don't think its too hot.
I'm stumped.

 

[Mac525]

Re: Engine issues

any luck so far???

 

[tedhrs]

Re: Engine issues

any luck so far???

Okay, here's an update to my issues.
Took to the mechanic guy and calls me and tells me he is going to rebuild the carb based on the description's i gave him. He pulls it apart and finds that one of the jets is clogged and that the bowl was disgusting with crap and ethanol stuff and water in it.

I went tonight and he and I took it out so he could see if still did it under load.

started up okay in the water, idled out a little bit and then went to give it throttle...missing like a son of a gun. He works the throttle some up and down and then pops the hatch with it running about 1700 rpm and starts unplugging spark plug wires from the cap. tells me to come take a look. he has 3 wires off all leading from the port side. all three are not firing he says inside the cylinder. There is spark coming from the cap but no spark coming from the plug due to water getting in there.

Tells me to shut it off and listen to the sound coming out of the carb. So i do and i hear a hissing sound like steam or something coming out.
Says you got a blown head gasket on that side. Says Lets replace both of them and clean out the risers/manifolds while we got em off. Tells me it should only take us about 5-7 hours with both of us working and i'll charge ya $200 plus a cooler of beer.

So, the boat is gonna sit til i feel like fixing it. Oh well.

 

[tedhrs]

Re: Engine issues

would a blown head gasket cause this issue that i'm having?

 

[snowman51789]

Re: Engine issues

Thank you for posting your results to your problem. I am havin problem with my boat ant I have found at least 7 threads were someone is havin the exact same problem but the fix there boat and never post the results leavin others in the dark. So thank you. Haha