Mag 350 mpi no power

skennelly

Planned a boat trip today.  Boat wouldn't go above 3000 rpm and didn't have any power.  We aborted the mission.  Admiral said it smelled like gas and when I was running at the dock noticed a gas sheen on the water.

My vessel view is also complaining that the engine warning alarm is not working...I do not hear any beeps.

I'm thinking I'll do a complete tuneup.  Plugs, wires, cap rotor.  Fuel filters I changed already this spring.

I'm worried about the gas in the exhaust.

YYZRC

I had this when a plug wire was off. Your plan for plugs/wire/cap/rotor makes good sense. 

LaRea

Before you replace the plug wires, check them for chafing or other damage.  

skennelly

@LaRea - I have never changed the wires since owning the boat so I plan to just replace.

Distributor cap n rotor.  $30 vs $70.  Both have brass contacts.  What's the difference?

LaRea

Definitely replace the plug wires.  What I'm saying is:  before you remove any wires, inspect all of them carefully.  If there's any chafing or damage, figure out why it happened so you can avoid it with the new wires.  

skennelly

@LaRea - Oh yes absolutely great advice.

skennelly

@LaRea - any thoughts on the distributor cap n rotor.  $30 vs $70?

Aqua_Aura

skennelly said:

@LaRea - any thoughts on the distributor cap n rotor.  $30 vs $70?

Can you give more info like a link. Is one Quicksilver and one Sierra?

LaRea

I'd be fine with Sierra.  

YYZRC

Search on here for the eBay cap and rotor. Seller was jeepster or something. Great piece great price, a bunch of members purchased. 

skennelly

@Aqua_Aura

https://www.amazon.com/dp/B01MSCURTJ/ref=cm_sw_r_cp_apa_glt_fabc_TG42V4S7DQBVAFNJ1D5F

https://www.ebay.com/itm/MERCRUISER-MPI-FLAT-V8-DELCO-CAP-ROTOR-898253T29-8M0060495-8M0061335-/263177120737?mkcid=16&mkevt=1&_trksid=p2349624.m46890.l49286&mkrid=711-127632-2357-0

Found the Jeepster one.  I just don't see the diff between the $19 ebay vs this one for $39

https://www.ebay.com/itm/MerCruiser-MPI-Distributor-flat-V8-Delco-Cap-Rotor-898253T29-8M0060495-8M0061335-/322007035433?mkcid=16&mkevt=1&_trksid=p2349624.m46890.l49286&mkrid=711-127632-2357-0

Aqua_Aura

The seller for $19 has a lot of negative seller feedback. They have a 97 percent rating but they seem to have excessive negative feedback. That might be why the parts are cheap they probably don't source their stuff well and it gets them negative feedback 

It's only $20 more for a part you may never replace for many years. 

YYZRC

I had the jeepster ones in the 330 and they worked great. Would have used them in the 350 but he wouldn’t ship to Canada. 

skennelly

I realized that I purchased a new cap n rotor last August...so not even a full season.  To be safe I'm going to order that gojeepster one.

Liberty44140

Just returning from a trip and we were running with an SR 32 with 350’s. He stalled on one engine and couldn’t keep it running. Limped in on one. I asked about cap/rotor and he confirmed his are barely 1 season old. Well, they were new but still the rotor shorted. Replaced it and all good for the rest of the trip.  We ran 3 hours in pouring rain and of course SR doesn’t do camper back like Rinker so all the rays in our 8 boat group were like wet rats! Guessing water got in since it was so new.

skennelly

So I did a compression test today.  175 psi on 6 cylinders.  2 cylinders were 177 psi...so really good compression.

Changed plugs and wires and immediately I noticed it running better.  Will be taking it for a cruise this evening for the real test.

2 plugs were physically damaged at the terminals...so it's very possible I was only running on 6 cylinders...thus the no power.

skennelly

Took the boat out for a run.  Power is back... every seems to be good now.

Liberty44140

That’s great! Glad it was cheap and simple 

reneechris14

Nothing like the felling of power.