Weird 525EFI Question

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09-18-2014 | 09:08 PM

#11

flatlanderbill

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From: Groton, CT.

Quote:

Originally Posted by bripar77

If the engine still revs ok not under load (in neutral) good chance you have a vacuum leak from probably a hose that came off somewhere. Check for vacuum small hoses that
that would change the timing. Sounds like what happen to me once. Even had my mechanic in the boat and he could not figure it out. A friend found it. Small 1/8 vacuum line under the whipple charger in the manifold. It was effecting the timing through the ECU. It would rev up fine in neutral but once we tried to get on plane it would lay down. Not 525's but sounds the same

Will definitely be looking for that tomorrow! Thanks for the lead! Fingers crossed ! Seemed to run up normally until the low water pressure beep at about 4000 rpm in neutral on the lift with the lowers dipped in the water . At least I am assuming that's what's the beep was . Have heard it before when getting too excited revving them up on the lift.

09-18-2014 | 09:09 PM

#12

PARASAIL941

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From: anna maria island,fl

Bripar77 may be on the right track. Backfire may have blown hose off fuel regulator. Hopefully nothing internal. Good Luck!!!

09-18-2014 | 09:25 PM

#13

VoodooRob

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From: Cleveland Ohio

Have a scan done. On our 525s once in awhile starboard would make a metallic tap sound while getting on plane only. Sounded like it was in the exhaust header. The tap would only make the noise one or 2 times when getting on plane, otherwise engine performed fine. Turned out it was a bad cam sensor.

Last edited by VoodooRob; 09-18-2014 at 09:28 PM.

09-19-2014 | 06:29 AM

#14

D Harry

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From: Malta - Europe

I had the same problem once, it was that the mechanic's fault by putting the number 5 plug lead into the 7 and vice versa. Idle was fine, no power and it did backfire.

09-19-2014 | 06:37 AM

#15

Unlimited jd

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From: Taunton Ma

Quote:

Originally Posted by D Harry

I had the same problem once, it was that the mechanic's fault by putting the number 5 plug lead into the 7 and vice versa. Idle was fine, no power and it did backfire.

If the wires were swapped it was not fine at idle. There is a pretty distinct vibration to a misfiring engine.

09-19-2014 | 06:46 AM

#16

D Harry

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From: Malta - Europe

Believe me it did idle fine, and that was one of the reasons I took quite a while to solve the problem. but it use to backfire also on idle

Last edited by D Harry; 09-19-2014 at 06:48 AM.

09-19-2014 | 07:02 AM

#17

squaz

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Joined: Jun 2006

Posts: 66

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From: Kennett Square

I had a 500 EFI that had the same simptons .turned out it was the coil pickup that is under the distributor cap.You have to pull the dist.and knock the pin out of the gear and slide the shaft out to get to it.I to replaced everything else till someone mentioned it here on OSO.Just a thought