PDA

View Full Version : hot start issue


canada air
09-20-2009, 11:20 PM
1995 maristar 275hp tbi my boat started having issues strarting when hot. cools down starts fine. checked battery and almost burnt finger on posts they were so hot. is it starter issue, maybe just dirty posts or do i have leaky manifolds leaking water in cylinders.

JimN
09-20-2009, 11:40 PM
Is it a problem with cranking when it's hot or does it need to crank a long time before it starts? If you need to crank fro a long time, hot terminals is normal. If you need to crank it a long time before starting, that's not. Crack the throttle next time and see if it fires right up. If it does, take a whiff of the exhaust and of it smells strongly of gas, check your ECT (Engine Coolant Temperature) sensor's resistance. It's the two wire sensor with one yellow and one black wire. The one-wire sensor is only for the gauge and doesn't affect the motor's operation. High resistance (more than a few thousand Ohms) indicates a failed sensor and would make the ECM think the temperature is extremely low, causing it to deliver more fuel than necessary and when this happens, it's far too rich to start with the available air charge. Opening the throttle a little adds air and makes the air:fuel ratio closer to normal. It's a cheap part and can easily be replaced using one wrench.

canada air
09-21-2009, 10:52 AM
sorry i may not have mentioned that the engine barely cranks over or won't crank when hot. it almost seems like either engine is siezed or starter gets hot. but they battery posts are smokin hot. checked both batteries in garage last nite and they have 12.79 and 12.97 v on voltmeter

canada air
09-21-2009, 11:08 AM
i was thinking i would clean up battery posts and cables see if that helps. then maybe try rebuild on starter. how would i check for water in cylinders from manifold leak. this boat has closed cooling due to the first 2 years it was in salt water and than fresh since.

Shane21
09-21-2009, 05:04 PM
I have a '91 Maristar 240SC and have the exact same problem. I've been told it may be due to timing. If the timing is set so that it starts well when cold (which mine does), as the engine heats up, the timing advances and it makes it harder to start when hot. I actually melted a post on a battery once before fighting this issue. I've got some pics I may be able to dig up somewhere. I was also told to perhaps change out the ground wire. I recently replaced the starter solenoid. I've had my starter in a shop and had bushings replaced. They said the starter was fine. I'm likely going to put a new starter on it for next year anyway and see. Bottom line, I still have that issue and would be curious if you find any answers.

JimN
09-21-2009, 06:34 PM
Barely cranking is a different issue. Is there any way you could use a digital camera to record audio while you crank it hot (video along with it is fine and can even help pinpoint the problem)? You Tube or some other way is fine and when you don't need that video online, you can delete it.

If it cranks hard and may be lumpy, I would check timing. All EFI motors from that era should be at 10BTDC in service mode. You can't verify base timing without that.

Tom Jones
09-21-2009, 07:33 PM
Hey Jim,
I have a 2004 310 TBI, the dealer set the timing at 8 degrees (I believe it is supposed to be 10 degrees at 1000 RPM. I seem to have an irratic idle now (was good before). Any thought as to what affect the the timing might have on the idle speed (idles anywhere from 650 - 1080).

JimN
09-21-2009, 07:51 PM
Hey Jim,
I have a 2004 310 TBI, the dealer set the timing at 8 degrees (I believe it is supposed to be 10 degrees at 1000 RPM. I seem to have an irratic idle now (was good before). Any thought as to what affect the the timing might have on the idle speed (idles anywhere from 650 - 1080).

It should be rock solid at about 700 but If you connect a timing light without putting it in service mode, you should see the timing mark jump around a bit. That's normal.

The timing shouldn't have that much effect if the difference was only 2 degrees and it should never go that high. Do you have Perfect Pass or something like it? Make sure that isn't causing the high idle.

canada air
09-21-2009, 08:36 PM
it does not turn over it is like seized engine than after cooling it fires up with slight drag of starter. we idle back to marina to let ballast drain and we shut off and it starts right up. it only seems to act up when it has been working (1500lbs ballast and three wakeboarders). i am an hour away from boat and will not get up there until weekend. our outside temps are starting to drop. sept has been awesome this year. 13hours on boat more than last september. i was thinking next weekend of bringing starter in. today i cleaned battery posts. and then i will clean cable ends. batteries checked out at battery shop when load tested. i have code reader and set timing last year at 10. tried it at 12 and would start like almost dead battery. had ecm updated few years back an that solved the having to move throttle ahead to start after boarding

hester
09-21-2009, 09:43 PM
When we rode a bunch and turned off my 91 351 it would not start or even attempt to turn over. When we let it cool down for a while it would start perfectly. Like you I tried everything and eventually replaced the starter which fixed it 100%. Not saying this is your problem but worth checking.

Could have rebuilt like many on here suggested but I wanted to get something new. The starter (updated permanent magnet style) from skidim works perfectly and turns the motor over like a champ. Here are a couple of pics for comparison.

JimN
09-21-2009, 09:44 PM
it does not turn over it is like seized engine than after cooling it fires up with slight drag of starter. we idle back to marina to let ballast drain and we shut off and it starts right up. it only seems to act up when it has been working (1500lbs ballast and three wakeboarders). i am an hour away from boat and will not get up there until weekend. our outside temps are starting to drop. sept has been awesome this year. 13hours on boat more than last september. i was thinking next weekend of bringing starter in. today i cleaned battery posts. and then i will clean cable ends. batteries checked out at battery shop when load tested. i have code reader and set timing last year at 10. tried it at 12 and would start like almost dead battery. had ecm updated few years back an that solved the having to move throttle ahead to start after boarding

If you have a pair of mechanic's gloves, pull some of the spark plugs and crank it. If it smells strongly of gas, you may have an injector leak.

JimN
09-21-2009, 09:45 PM
When we rode a bunch and turned off my 91 351 it would not start or even attempt to turn over. When we let it cool down for a while it would start perfectly. Like you I tried everything and eventually replaced the starter which fixed it 100%. Not saying this is your problem but worth checking.

Could have rebuilt like many on here suggested but I wanted to get something new. The starter (updated permanent magnet style) from skidim works perfectly and turns the motor over like a champ. Here are a couple of pics for comparison.

The '94 has a gear reduction starter already, yours didn't.

Cranks nice, doesn't it?

Tom Jones
09-22-2009, 12:26 PM
It should be rock solid at about 700 but If you connect a timing light without putting it in service mode, you should see the timing mark jump around a bit. That's normal.

The timing shouldn't have that much effect if the difference was only 2 degrees and it should never go that high. Do you have Perfect Pass or something like it? Make sure that isn't causing the high idle.

Thanks Jim,
I do have a PP which has been doing some goofy things lately i.e. screen going black, jumping to a different readout by itself, etc.
Dealer changed the timing this morning back to 10' in service mode. Funny thing was the timing changed by itself after he set it. He had to set it again and it seemed to hold?
Idling around 860 now and sometimes 770 and sometimes 650? Could it be a dirting IAC?
I'll check the throttle linkage and PP though.
Factory also had a 140' thermostat in it, Dealer changed it to 160' which is when the erratic idle started.

Tom

JimN
09-22-2009, 04:00 PM
Thanks Jim,
I do have a PP which has been doing some goofy things lately i.e. screen going black, jumping to a different readout by itself, etc.
Dealer changed the timing this morning back to 10' in service mode. Funny thing was the timing changed by itself after he set it. He had to set it again and it seemed to hold?
Idling around 860 now and sometimes 770 and sometimes 650? Could it be a dirting IAC?
I'll check the throttle linkage and PP though.
Factory also had a 140' thermostat in it, Dealer changed it to 160' which is when the erratic idle started.

Tom

If I was working on it, I would have checked the oil cooler first, then the timing and if that was stable, great. If it isn't stable, I would hook it up for diagnostics and see what the sensors are doing. If I see one that's flakey at idle when it shouldn't change at all (like the TPS and MAP sensors), I would check them out. It is possible that the IAC is sticky but that can be verified with the diagnostic computer because the IAC can be functioned manually (open, close and repark). If anything seems weird, it can be addressed.

What about fuel quality? The pressure was checked but did you take a fuel sample? If it's getting water, it won't burn as evenly and the ECM may need to "hunt" for the right RPM. I don't think the thermostat would make this happen. I would also cehck all of the ground wires and ground points.

Tom Jones
09-22-2009, 07:32 PM
Thanks Jim,
that is very helpful
One thing though, where is the oil cooler and how do you check that?
I know there is a transmission fluid cooler.

Tom

JimN
09-22-2009, 08:00 PM
Thanks Jim,
that is very helpful
One thing though, where is the oil cooler and how do you check that?
I know there is a transmission fluid cooler.

Tom

Same thing. Remove the hose on the hill end and look or feel around for leaves, sticks, etc. Anything in there can be a problem.

Tom Jones
09-23-2009, 10:16 PM
It should be rock solid at about 700 but If you connect a timing light without putting it in service mode, you should see the timing mark jump around a bit. That's normal.

The timing shouldn't have that much effect if the difference was only 2 degrees and it should never go that high. Do you have Perfect Pass or something like it? Make sure that isn't causing the high idle.
Jim,
thanks for your help, you were right
the perfect pass servo motor had spun around on the cooling hose which must have been binding the cable, I took the boat out for a ski tonight and had no problem with the idle which is about 670 RPM, right where you said it should be.
I also checked the cooler and found a large piece of the impeller in there, guess I better change it. Dealer set the base timing back to spec. at 10' a couple of days ago. Seems to have lots of power and runs smooth. I also put some gas line antifreeze iin the gas tank to take care of any water that might have been in the tank.