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73blue
07-15-2010, 02:21 PM
Ok so I've searched all over these forums (been a huge help btw) but I can't find my problem or a solution anywhere. I have a 2004 X-10 with the MCX engine, app 400 hours. This spring the boat overheated and I replaced the thermostat and water pump. No more cooling problems. Now the boat starts fine, runs smooth until warm, then the issues begin.
On takeoff the boat really bogs down and acts like its choking out. Every once in a while it will slightly backfire. When I turn it off and restart it the idle drops to 300 rpm. With a slight nudge of the throttle it will increase to 600 and stay there. I think I've lost a couple mph top end, but I've propped down and weighted, so that may be in my head. It does top out about 4600 rpms. When I'm riding behind it (I'm 260, so it puts a load on it) there is a little smoke but no soot buildup or anything. And man is it drinking gas!
Obviously something is throwing off the air/fuel ratio and feeding the engine way too much fuel. Here's what I've done/checked so far:
Changed spark plugs
Cleaned K&N
Checked Oil
Checked fuel pressure @ key on/engine off, idle, 1/2, and w/o
Checked TPS w/ volt meter
Changed Coolant temp sensor
Run Seafoam through it
Finally had a dealer plug his comp in- no codes, everything looked normal on the hose

I thought it may be the MAP sensor but the tech said it would def throw a code. He seemed to think it was a leaking injector or the IAC. I put the fuel pressure gauge on, turned the key on to pressure up, turned key off, and it bled down about 1 lb/min. My mechanic friend said a leaking injector would be a much faster bleed, which leaves me with the IAC. Figured I'd check with yall first before I kept jumpin at things.

notnowgus
07-15-2010, 10:42 PM
I know this sounds crazy, but have you disconnected the battery for a minute or two to see if that changes anything? When all else fails, disconnect!

73blue
07-17-2010, 02:55 PM
To update: Changed the IAC, no change in engine trouble. Any help would be appreciated.

73blue
07-20-2010, 10:14 PM
Unhooked battery, changed MAP, still nothing. Any ideas?

73blue
07-22-2010, 02:21 PM
Ok now I'm confused. Saw some threads on here that said my fuel pressure at the rail should be around 58 psi, which is what I have at key on. My owner's manual says 35-45 psi. Which is it? Also checked the pressure again under load when the boat was acting up, slight oscillation in needle at idle and wot, but at 2000 rpms it was bouncing from 40-70 psi. Whats the deal? Fuel pump? Pressure Regulator? Any help would be appreciated.

2000XPSD
07-22-2010, 03:04 PM
check the IC and for the a dirty IAC
Fuel pressure should be with key on engine off 41-47psi

73blue
07-22-2010, 03:19 PM
Already put in new IAC (see earlier post). IC? Sounds like fuel pressures too high. Regulator?

mgurley
07-22-2010, 04:11 PM
Did you remove any plug wires? Did any plug/wires get unusually wet?

73blue
07-22-2010, 06:48 PM
I've checked the plugs. No noticible difference with any. They look normal.

JimN
07-22-2010, 07:08 PM
Ok so I've searched all over these forums (been a huge help btw) but I can't find my problem or a solution anywhere. I have a 2004 X-10 with the MCX engine, app 400 hours. This spring the boat overheated and I replaced the thermostat and water pump. No more cooling problems. Now the boat starts fine, runs smooth until warm, then the issues begin.
On takeoff the boat really bogs down and acts like its choking out. Every once in a while it will slightly backfire. When I turn it off and restart it the idle drops to 300 rpm. With a slight nudge of the throttle it will increase to 600 and stay there. I think I've lost a couple mph top end, but I've propped down and weighted, so that may be in my head. It does top out about 4600 rpms. When I'm riding behind it (I'm 260, so it puts a load on it) there is a little smoke but no soot buildup or anything. And man is it drinking gas!
Obviously something is throwing off the air/fuel ratio and feeding the engine way too much fuel. Here's what I've done/checked so far:
Changed spark plugs
Cleaned K&N
Checked Oil
Checked fuel pressure @ key on/engine off, idle, 1/2, and w/o
Checked TPS w/ volt meter
Changed Coolant temp sensor
Run Seafoam through it
Finally had a dealer plug his comp in- no codes, everything looked normal on the hose

I thought it may be the MAP sensor but the tech said it would def throw a code. He seemed to think it was a leaking injector or the IAC. I put the fuel pressure gauge on, turned the key on to pressure up, turned key off, and it bled down about 1 lb/min. My mechanic friend said a leaking injector would be a much faster bleed, which leaves me with the IAC. Figured I'd check with yall first before I kept jumpin at things.

The MAP sensor shouldn't have a problem when the only incident that you can think of is an overheat. One that would affect the air/fuel mix is the ECT (Engine Coolant Temperature) sensor. If the motor was hot enough, it's possible that the harness to the ECT melted and the wires shorted together, causing the sensor to read erroneously. Normally, the wires shorting would cause an overheat indication (low resistance - high temperature indication) but it's also possible that the sensor is bad. If you can't read a code, do a visual check of all wiring that is in contact with the motor.

Do a compression test, if this hasn't been done yet.

73blue
07-22-2010, 07:17 PM
I replaced the ECT and checked the connections a few days ago. I'll try to do a compression test tomorrow. What do you think about the fuel pressure? Thanks for the responses btw.

JimN
07-22-2010, 07:58 PM
I replaced the ECT and checked the connections a few days ago. I'll try to do a compression test tomorrow. What do you think about the fuel pressure? Thanks for the responses btw.

The first thing I would do is stop throwing parts at it. Anything that causes this will be measurable. That means a code will show up if it's a sensor. The IAC should be re-parked if a new one is installed and it won't necessarily go to the correct position immediately. This doesn't send any feedback to the ECM- it just does what its told and there's a "home position" that is used as the reference point.

notnowgus
07-22-2010, 11:33 PM
I have seen oxygen sensors on sbc's go bad without giving a trouble code (in trucks). Did the 04 MCX have an O2 sensor?

2000XPSD
07-23-2010, 01:50 PM
Already put in new IAC (see earlier post). IC? Sounds like fuel pressures too high. Regulator?

ic= ignition control reference....but after reading your post again don't bother checking, it's tough to check it. the IC btw is where the injectors get there pulse timing...via the ecm

but sounds like high fuel pressure...check real good for vacuum leaks. the fuel reg is vacuum driven off of intake manifold.
Compression test like jimn said is a good idea too...a burnt or bad valve = high manifold pressure = high fuel pressure

check the pcv valve for the hell of it...and wiring like jimn said but add to the list vacuum hoses too

and to reset the IAC pintle postion:
1) turn off ign for 10 sec
2) start eng for 5 sec
3) ign off for 10 sec
4) restart and check idle...that's it

the pintle distance should be preset from the factory but if you want to check it then it should be 28mm tip to body flange

2000XPSD
07-23-2010, 01:51 PM
I have seen oxygen sensors on sbc's go bad without giving a trouble code (in trucks). Did the 04 MCX have an O2 sensor?

no o2 sensors in a 04

73blue
07-23-2010, 07:18 PM
Compression test looks good. The plugs, put in 2 weeks ago, now have a lot of build up. I'm assuming from the extra fuel they're getting. Gonna test the vacuum pressure tomorrow. Any way to check this with no gauge? Gonna have to borrow one if not. Also any tips on checking the pcv valve? On the bright side, its been a very educational process.

Engine Nut
07-23-2010, 09:04 PM
I replaced the ECT and checked the connections a few days ago. I'll try to do a compression test tomorrow. What do you think about the fuel pressure? Thanks for the responses btw.

See the attached fuel pressure chart.

2000XPSD
07-24-2010, 03:35 PM
See the attached fuel pressure chart.

Huh??? Never seen that sheet before and totally diff from my paperwork. All my stuff is from MC tho. I wonder what is correct now too
Never the less he has a 40-70psi swing in FP...not good

To check to pcv just shake it...you hear a rattle it's good. Simple

To check vacuum without a gauge you can do two things...spray carb cleaner or sim around and listen for a jump in rpm. This of course is going to make a mess on a nice powder coated engine. Or two take a small propane bottle (like for soldering) and put a hose on it. Then wave it around all intake fittings,joints and what not and listen for a rpm jump again. Just be careful with propane and a boat engine compartment if you know what I mean

Good news on the comp test tho...

JimN
07-24-2010, 03:46 PM
Huh??? Never seen that sheet before and totally diff from my paperwork. All my stuff is from MC tho. I wonder what is correct now too
Never the less he has a 40-70psi swing in FP...not good

To check to pcv just shake it...you hear a rattle it's good. Simple

To check vacuum without a gauge you can do two things...spray carb cleaner or sim around and listen for a jump in rpm. This of course is going to make a mess on a nice powder coated engine. Or two take a small propane bottle (like for soldering) and put a hose on it. Then wave it around all intake fittings,joints and what not and listen for a rpm jump again. Just be careful with propane and a boat engine compartment if you know what I mean

Good news on the comp test tho...

EngineNut is in the technical department at Indmar- It's good info.

TX.X-30 fan
07-24-2010, 04:24 PM
Is it the original fuel pump?? I would bet its on its way out if so. I had some similar issues before I replaced the pump.... bogging and not running right. I also had pressure at the rail on the bad pump. He!! its 100 bucks and if its not bad on an 04 MCX it will be soon.

2000XPSD
07-24-2010, 07:20 PM
I don't doubt EngNut, I know he knows his shxt. Just found it weird indmar is so diff than MC.

Tx.x30- yeah it's prob the pump or reg. Poor guy already fired the parts cannon at it once tho...just trying to nail it for sure first before "fire 2!".

Engine Nut
07-24-2010, 10:07 PM
I don't doubt EngNut, I know he knows his shxt. Just found it weird indmar is so diff than MC.

Tx.x30- yeah it's prob the pump or reg. Poor guy already fired the parts cannon at it once tho...just trying to nail it for sure first before "fire 2!".

If your injectors have a black metal body like in the picture marked 3 bar (on the left) the fuel pressure is a nominal 40 PSI. If they are gray plastic like the one in the picture marked 4 bar (on the right), the pressure is 60 PSI. We started using the 4 bar fuel system in 2004.

Tom Jones
07-25-2010, 10:59 AM
I've been watching this post and I thought it was time I jumped in here. I have an 04 TBI and am having a similar issue with a run rich condition. I have also checked and cleaned eveything and still have the problem. Do your plugs have a black soot on them? Mine do. At idle the engine will intermittently stall but catches itself and does not shut down. It seems to run fine above idle except ever once in a while when I am skiing the slalom course I can smell gas when I stop skiing and the boat is idling. I ran my gas tank dry once over a year ago and I have checked the fuel pressure at idle and it is good at 30PSI. After looking at this post I'm thinking perhaps it is a faulty fuel pump that hasn't shut down yet but maybe is acting up with fuel pressure spikes or lulls.
I've seen other posts where it seems NAPA has a fuel pump motor that will replace the original. What is the part from, which model car? I am going to rebuild my fuel pump and see if it cures the problem.

2000XPSD
07-25-2010, 11:32 AM
AC delco ep356 = P74122 in napa

Thanks enut for pointing that out

Tom Jones
07-25-2010, 12:41 PM
Thanks for the info.

TX.X-30 fan
07-25-2010, 02:30 PM
I never heard of injector problems on TT before but I ain't doubting it now. Should he change them all or try one by one?

73blue
07-25-2010, 04:40 PM
Ok, checked the pcv valve. It rattled. Sprayed carb cleaner around vacuum fittings with no noticible change in rpm. As an aside, how does the regulator use vacuum pressure if there is no return line to it. Only hose leaving the regulator is the fuel line. I do have the grey plastic injectors also. Starting to sound like a fuel pump, but I'll listen to more suggestions. Apparently I'm not the hottest plug in the block.

JimN
07-25-2010, 06:19 PM
I never heard of injector problems on TT before but I ain't doubting it now. Should he change them all or try one by one?

They can be checked for the spray pattern without needing to replace any. If they're bad, then replace them.

Engine Nut
07-25-2010, 11:00 PM
Ok, checked the pcv valve. It rattled. Sprayed carb cleaner around vacuum fittings with no noticible change in rpm. As an aside, how does the regulator use vacuum pressure if there is no return line to it. Only hose leaving the regulator is the fuel line. I do have the grey plastic injectors also. Starting to sound like a fuel pump, but I'll listen to more suggestions. Apparently I'm not the hottest plug in the block.

That system is what is referred to as a returnless system.The fuel pressure regulator is a mechanical regulator and not vacuum actuated. The regulator is at the fuel pump.

73blue
07-26-2010, 08:18 AM
Ok so is there any way to tell if its the regulator or pump? I've seen the threads on replacing the pump, but nothing on the regulator. Can you buy an aftermarket version?

2000XPSD
07-26-2010, 12:52 PM
. As an aside, how does the regulator use vacuum pressure if there is no return line to it. Only hose leaving the regulator is the fuel line.

it's a diaphragm relief valve w/fuel pressure on one side and intake and spring pressure on the other. as vacuum drops fuel pressure goes up.

on returnless the reg is part of the outlet filter on the pump...i think
on return types the reg it on the fuel rail

73blue
07-26-2010, 09:02 PM
Ok, I changed the fuel pump. I know, I know, but the poor boat was just sittin there, and I want to ride tomorrow, and I read how you guys all have fancy aftermarket pumps, and I got a little jealous, and maybe a little impatient, and I did it. Long story short, didnt help (cuss, cuss, cuss). I havnt fully tested it (I'm riding tomorrow, no matter what) but I hooked the pressure gauge up and same old story. 56-58 psi @key on, 58 psi @ idle w/ some oscillation, 40-80 psi @ 2000rpms, 58 psi @wot w/ only slight oscillation. It didnt seem to want to backfire like it had been on initial acceleration. It still had a very low idle (300rpm) on warm restart a couple of times, but now it corrects itself after 10-15 sec. Anything I'm missing (and feel free to berate my lack of willpower)?

73blue
07-27-2010, 04:24 PM
Ok I think I may have done it. After failing to find an aftermarket regulator, it hit me. Most of the time the pump goes bad. After a quick call to my local dealer, who shall remain nameless for reasons which will soon become clear, I found that they had a stack of old fuel pump modules (go figure) waiting to be hauled off. After snaking a couple from the pile this morning, unbeknownst to them (wink, wink), I salvaged a regulator off one and installed on my module. Boom. Steady pressure @ key on, idle, 2000 rpm, and wot. I'll conduct further testing this afternoon, but it looks good so far. I appreciate yalls help.

2000XPSD
07-28-2010, 01:53 AM
nice...if FP is steady now she should be ok

André
07-28-2010, 11:43 AM
Ok I think I may have done it. After failing to find an aftermarket regulator, it hit me. Most of the time the pump goes bad. After a quick call to my local dealer, who shall remain nameless for reasons which will soon become clear, I found that they had a stack of old fuel pump modules (go figure) waiting to be hauled off. After snaking a couple from the pile this morning, unbeknownst to them (wink, wink), I salvaged a regulator off one and installed on my module. Boom. Steady pressure @ key on, idle, 2000 rpm, and wot. I'll conduct further testing this afternoon, but it looks good so far. I appreciate yalls help.

Nice move!;)
A question for EngineNut.Is the infamous fuel pump design from Indmar or from MC?

TX.X-30 fan
07-28-2010, 01:21 PM
Nice move!;)
A question for EngineNut.Is the infamous fuel pump design from Indmar or from MC?




The ahbama administration I believe.

JimN
07-28-2010, 02:43 PM
Nice move!;)
A question for EngineNut.Is the infamous fuel pump design from Indmar or from MC?

Alan tested it for more than 3 years before presenting it to the CG and MC signed on after they saw the test results. OTOH, this was pre-'99 by 4-5 years and I don't remember many pump failures before about '04, so that's a 9-10 year window for fuel changes to be made.

Indmar marinizes the drive systems and the boat manufacturer handles the rest of the design and systems.

2000XPSD
07-29-2010, 01:29 PM
Ok I think I may have done it. After failing to find an aftermarket regulator, it hit me. Most of the time the pump goes bad. After a quick call to my local dealer, who shall remain nameless for reasons which will soon become clear, I found that they had a stack of old fuel pump modules (go figure) waiting to be hauled off. After snaking a couple from the pile this morning, unbeknownst to them (wink, wink), I salvaged a regulator off one and installed on my module. Boom. Steady pressure @ key on, idle, 2000 rpm, and wot. I'll conduct further testing this afternoon, but it looks good so far. I appreciate yalls help.

What ever happened??? She all better now???

73blue
07-29-2010, 02:33 PM
Got another water test this afternoon :) but yeah, I think so. I'm being cautiously optimistic after dealing with it so long. Would have been a lot worse and more expensive (even with a couple rounds through the "parts cannon") without yall's help tho.

73blue
08-01-2010, 11:32 PM
Well it looks like we will be cranking up the old diagnostics tests again tomorrow. Boats running bad as ever. I guess I'll run thru the basics one more time to make sure I didnt miss something. Then maybe I'll "forget" to put the plug in. JK

JimN
08-01-2010, 11:53 PM
Well it looks like we will be cranking up the old diagnostics tests again tomorrow. Boats running bad as ever. I guess I'll run thru the basics one more time to make sure I didnt miss something. Then maybe I'll "forget" to put the plug in. JK

Where are you, in the Southeast? If you're close enough to another dealer, it may be worth a road trip.

73blue
08-02-2010, 08:26 AM
Not a bad idea. One more thing that hit me in my sleep. Lets say, purely hypothetically speaking, someone had bypassed their emergency shut-off switch by hooking the wires together after the switch went bad on the lake and then just left it that way. Could that possibly cause these or similiar problems in this hypothetical boat? I'm not sayin, I'm just sayin.

JimN
08-02-2010, 09:11 AM
Not a bad idea. One more thing that hit me in my sleep. Lets say, purely hypothetically speaking, someone had bypassed their emergency shut-off switch by hooking the wires together after the switch went bad on the lake and then just left it that way. Could that possibly cause these or similiar problems in this hypothetical boat? I'm not sayin, I'm just sayin.

If it was spliced badly and the voltage getting to the ECM is low, maybe. That wouldn't be a bad thing to check.

73blue
08-02-2010, 01:01 PM
Checked voltage on both sides, no problem. Another fuel pressure check, no problem. Headin to dealer.

73blue
08-12-2010, 01:03 PM
So the problem turned out to be the timing. Somehow got off by a full tooth. Cue the "should've been the first thing you checked" responses. I know this. I assumed the dealer had checked when he ran diagnostics, he assumed I had checked so he just did a quick code scan. I'm posting this (at the risk of personal embarassment) to hopefully help someone else out and to remind everyone of 2 things that will save you copious amounts of time and heartache:
1. Don't assume anything. If you didn't see it, question it.
2. I'm an idiot.

JimN
08-12-2010, 01:40 PM
So the problem turned out to be the timing. Somehow got off by a full tooth. Cue the "should've been the first thing you checked" responses. I know this. I assumed the dealer had checked when he ran diagnostics, he assumed I had checked so he just did a quick code scan. I'm posting this (at the risk of personal embarassment) to hopefully help someone else out and to remind everyone of 2 things that will save you copious amounts of time and heartache:
1. Don't assume anything. If you didn't see it, question it.
2. I'm an idiot.

You're not an idiot, your dealer/their mechanic is. Acquiring data is a TOOL, not a silver bullet. Scanning for codes SHOULD ONLY BE DONE AFTER BASE TIMING, COMPRESSION, FUEL PRESSURE AND THE OTHER BASIC TESTS HAVE BEEN COMPLETED!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

THEY assumed it was correct and it cost you money, time on the water and a buttload of frustration. Any parts they threw at it should cost you nothing.

For the little time it takes to verify timing, there's absolutely no reason for them to worry about whether you had/hadn't done it. It takes part of a minute.

munkymush
08-14-2010, 04:24 PM
so what caused it to be a tooth? out..what had jumped ?

2000XPSD
08-14-2010, 11:34 PM
So the problem turned out to be the timing. Somehow got off by a full tooth.

glad to hear its fixed...but i don't buy what the dealer says. you don't just magically jump a tooth, its very hard to do in a low rpm engine...and if you did it would start and run like total shxt. And if it actually did id inspect the distributor gear and take a look at the cam gear. You can jump a tooth on the timing gears but it take years of wear on the timing chain so that's just a bout impossible on a 04 boat motor.
I don't know...there has to be more to it.

73blue
08-15-2010, 08:24 AM
Good call guys. Took it out the night I picked it up. Bout 20 min in, boat shuts down. Stripped distributor gear. I checked the cam best I could and didnt see any damage. Replaced the distributor Friday. Any tips on how to put engine in service mode to double check timing?

chico
08-15-2010, 10:11 AM
Remove the DLC protective cap,insert paperclip into the openings for the white/black and black wires,labeled A and B,the idle will increase after putting into service mode.

JimN
08-15-2010, 10:30 AM
Good call guys. Took it out the night I picked it up. Bout 20 min in, boat shuts down. Stripped distributor gear. I checked the cam best I could and didnt see any damage. Replaced the distributor Friday. Any tips on how to put engine in service mode to double check timing?

Is the gear bronze or a metal that's almost black? If it's the latter, the teeth that came off need to be removed from the motor.

Did this boat sit for a long time?

When the paperclip is inserted, the idle may drop to about 400RPM- if it does, manually raise the idle to 1000RPM. You should see the timing light jump around before the paper clip goes in and the timing mark should be stable after.

2000XPSD
08-15-2010, 01:33 PM
Good call guys. Took it out the night I picked it up. Bout 20 min in, boat shuts down. Stripped distributor gear. I checked the cam best I could and didnt see any damage. Replaced the distributor Friday. Any tips on how to put engine in service mode to double check timing?


Well there is only a few things that will strip a gear...
1) not using a hardened gear with race cam...which we know you did not change the cam
2) distributor installed not fully seated...it sounds retarded but i've seen it done. the gears don't fully mess and the dist gear looses the battle. But this happens very quickly and your boat was running so probably not that either.
3) excessive bind from the oil pump...the oil pump is driven from the bottom of the dist gear. If the oil pump is having a issue of some sort it can jerk the gear around and chew it up...this might be something to monitor. usually the oil pump shaft will twist up after a complete failure
4)just a pos gear...i don't know what indmar used for material but from what jimn said it sounds like they switched to bronze at some point (which is smart)...hopefully that's just it, pop a new gear on it and away you go

i doubt you will get those pieces out of the oil pan...but i wouldn't worry to much as they probably fell straight into the sump and the p/u screen will keep them from getting sucked up. Change the oil tho...

JimN
08-15-2010, 03:08 PM
Well there is only a few things that will strip a gear...
1) not using a hardened gear with race cam...which we know you did not change the cam
2) distributor installed not fully seated...it sounds retarded but i've seen it done. the gears don't fully mess and the dist gear looses the battle. But this happens very quickly and your boat was running so probably not that either.
3) excessive bind from the oil pump...the oil pump is driven from the bottom of the dist gear. If the oil pump is having a issue of some sort it can jerk the gear around and chew it up...this might be something to monitor. usually the oil pump shaft will twist up after a complete failure
4)just a pos gear...i don't know what indmar used for material but from what jimn said it sounds like they switched to bronze at some point (which is smart)...hopefully that's just it, pop a new gear on it and away you go

i doubt you will get those pieces out of the oil pan...but i wouldn't worry to much as they probably fell straight into the sump and the p/u screen will keep them from getting sucked up. Change the oil tho...

I was only asking if it was bronze and neither Indmar nor MC change the distributor or cam AFAIK, so it's a stock gear. I'm not sure they can fall straight into the sump and I really wouldn't want to run it before at least trying to wash the pieces down there with oil. Then, I would want to put a magnet in the pan to attract whatever it can.

I'd like to see photos of the gear.

2000XPSD
08-15-2010, 05:07 PM
The gear is below the lifter valley inside a part of the block casting for the cam...there is a hole before the last cam journal that should let it drop...not saying it will for sure but I wouldn't freak to bad over it.

I got ya on the gear...so yeah I'd like to see a pic also...check the drift pin too

JimN
08-15-2010, 08:32 PM
I saw only one distributor gear that lost teeth and that one sat for a couple of years before he took it out and then it came in "for a tune-up" because it ran bad. I timed it by hand before cranking and if I could get it to run, it was OK for a few revolutions and then it either ran like crap or it just died. The timing mark was jumping all over the place and it was way off, so I removed the distributor, only to find 3 missing teeth. THEN he decided to tell me that it sat for all that time, although I had asked up front because I could smell that the gas was old.

Any idea if the distributor came out early in the process? One tooth at the distributor is odd-
the oil pump drive shaft has a slot in it, which makes it possible to go 180 degrees off or it's where it should be, unlike a Ford, which has a hex drive, so it can be off in multiples of 60 degrees.

I'd like to hear the cause of this- it's definitely a one-off.

73blue
08-15-2010, 10:10 PM
So some of this stuff is goin over my head, but here's what I know. The stock distributor actually stripped the gear in Summer 08. Car mechanic friend replaced it with a distributor from Advance so I could get back on the water. Pretty sure he may not have ever checked the timing, but it seemed to run fine. FF to end of last summer (09). After the season I took the boat in for its 300 hr service and winterization. In the past (after the first season) I have done the regular maintenance and winterization myself. The boat sat from Oct to April. I take it out, run it once, and have the overheat problem. The rear seal on the water pump was bad (maybe damaged when changing impeller?). After solving that issue I notice the lack of power. FF to Friday. Pull the distributor and 2-3 teeth are basically gone, the others are worn down (maybe from trying to crank it when it broke down on the water?) It was a black gear. Replaced the distributor and it seems to run fine. Tomorrow I will double check timing and change the oil (and hopefully get some pics for you). Also need a little help on DLC (to set service mode) and drift pin. Not sure what those are.

JimN
08-15-2010, 10:51 PM
So some of this stuff is goin over my head, but here's what I know. The stock distributor actually stripped the gear in Summer 08. Car mechanic friend replaced it with a distributor from Advance so I could get back on the water. Pretty sure he may not have ever checked the timing, but it seemed to run fine. FF to end of last summer (09). After the season I took the boat in for its 300 hr service and winterization. In the past (after the first season) I have done the regular maintenance and winterization myself. The boat sat from Oct to April. I take it out, run it once, and have the overheat problem. The rear seal on the water pump was bad (maybe damaged when changing impeller?). After solving that issue I notice the lack of power. FF to Friday. Pull the distributor and 2-3 teeth are basically gone, the others are worn down (maybe from trying to crank it when it broke down on the water?) It was a black gear. Replaced the distributor and it seems to run fine. Tomorrow I will double check timing and change the oil (and hopefully get some pics for you). Also need a little help on DLC (to set service mode) and drift pin. Not sure what those are.

If the distributor gear stripped, it's possible that some of the oil passages are clogged and IMO, it should have been checked for loose metal before it was run after the replacement was installed. A distributor gear is replaceable and it takes about a minute, so I don't know why the whole distributor was replaced.

The DLC is 'Data Link Connector' and is used for connection to a diagnostic computer or scan tool. It's located at the rear of the motor and has black & gray plastic. The GM motors with injection have a something called 'Spark stabilization' and this comes from the car programming- Americans like their cars to idle velvet smooth and this provides that function. It serves no other purpose but if you look at the timing mark with a timing light when Spark Stabilization is working, the mark jumps all over the place. Inserting a paperclip or other jumper into positions A and B defeats it, but without the diagnostic computer, the idle speed needs to be raised manually, to 1000 RPM.

A drift pin is the metal pin that is driven through the hole on the distributor gear, through the shaft and into the hole in the other side of the gear.

Was the gear worn on the bottom of the teeth, or the top?

73blue
08-16-2010, 05:04 PM
Got the timing set. Changing the oil later. The gear is worn in the middle but a little closer to the top, I'd guess.

http://www.mastercraft.com/teamtalk/picture.php?albumid=324&pictureid=1961

2000XPSD
08-16-2010, 11:27 PM
Well the drift pin is in, mesh looks ok...tough to say
Moly coat the new gear and break it in this time...run her at 1500-2000rpm for 20min and that will do it. Check the end play too. No thick oil