Gas issues at high temperature

[2ndtry]

Not sure which forum to use, just in case the motor is a Suzuki DF140, 2006

When the temperature if VERY hot (over 95), I sometimes lose priming after sitting with the motor off for a few minutes. What happens is the motor will turn on normally and I get about 50 yards before the motor dies. At this time the fuel bulb is soft, and I can usually get it running again after a few pumps. Without pumping the bulb the engine doesn't start.

This issue started 3 years ago, and I had the anti-siphon valve replaced. I didn't happen again until this year, but it has not been as hot in the meantime.

Any ideas? Thanks in advance.

 

[99yam40]

Re: Gas issues at high temperature

have you thought about testing the fuel system? http://forums.iboats.com/showthread.php?t=283363

 

[2ndtry]

Re: Gas issues at high temperature

have you thought about testing the fuel system? http://forums.iboats.com/showthread.php?t=283363

Thanks, it looks as if this may be the ticket. After reading the description, I realized I forgot to add that I can tell immediately after starting if I will have a problem if the motor revs briefly at idle. This was mentioned as one of he symptoms of a "boat side" issues.

 

[bigriver]

Re: Gas issues at high temperature

I am having the same problem. My motor is also a 2006 DF140. This past weekend the high temps were around 100 degrees. Yesterday we had no trouble out of the motor for the first couple hours of the morning, however once it got hot, the motor would die as I tried to get the boat up to speed, after it had been off for 30 minutes so. The bulb would be limp and it would take 20 or more pumps to get fuel flowing through it again. Once the motor is up to speed for more than a minute or two, I have never had it die. Its only within the first few seconds of takeoff.

I also fished with a buddy that has a 2010 DF140. On Saturday it was very hot too. His had not given us any trouble for most of the morning. When he started it once, it breifly reved up, which reminded me about what 2ndTry said. As he tried to get the boat up to speed, it died! Again, his bulb was flat, and it took several pumps to get the fuel flowing again.

Anyway, it seems interesting that this has a direct correlation to the air temperature. Newer models are affected just like older models. I plan to check for possible air leaks, but it seems odd that we don't experience problems in normal and cooler tempertures. And since it doesn't look like the temps are going to cool down anytime soon, I would like to find a fix.

 

[2ndtry]

Re: Gas issues at high temperature

Things are a bit cooler around here, and it doesn't seam as bad now. Before I read the post by bigriver, I just figured I had an issue with the gas lines on the boat side. Very weird that another DF140 has the exact same problem.

I am now conditioned to pump the bulb if the engine revs at startup. Like bigriver, it never dies if its been running more than a minute.

If you figure anything out, let me know.

 

[Peter Eikenberry]

Re: Gas issues at high temperature

A couple of suggestions:

1. have the fuel system pressure tested for leaks. You may have a pinhole leak that is causing the line to lose pressure as the engine accelerates and the temp goes up. Especially check the bulb. It may have a hole in it.

2 Hot temps can cause vapor lock just like in a car. Does your fuel line run outside in the sun, or near any thing that gets hot? keeping the line cooler may help.

3. Do you really need an anit-siphon valve? Anit-siphon valves are ONLY required if the fuel line runs down hill and can siphon the fuel out of the tank into the engine. If the fuel line runs uphill all the way to the engine you don't need the valve. Anti-siphon valves are notorious for clogging. Blow it out with compressed air. If you don't need it get rid of it.

However this sounds to me like loss of pressure in the fuel line and after a few minutes the engine is sucking air.

 

[bigriver]

Re: Gas issues at high temperature

I spoke with SuzukiAmerica (1-714-572-1490). Our problem is very common with their DF115 and DF140. Like Ike suggested, the problem concerns vapor lock, but within the fuel line or fuel pump beneath the cowling. Suzuki has come up with a fix for the problem, and is trying to get the problem rectified at the manufacturing point, but has not yet, so even newer model motors will/may have this problem.

The customer service person (Christine) that I spoke with was very helpful and knowledgeable about the problem. I think this was one of her "specialties". She explained that with my call, they would create a service ticket, or something to make a record of my call. Then I was to call an authorized service center, and take them the motor so that they could replicate my problem (which I thought might be difficult to do in a tub). Anyway, she said that an experienced service center would have probably already dealt with this problem. Then the service center would have to call SuzukiAmerica to report the problem and to schedule a SuzukiAmerica technician to come to the service center to install an auxiliary fuel pump system. She said the service center personnel were not allowed to install the kit, only their technician could.

I explained that fishing was picking up and I would not be able to take my boat out of service for a week or two to get the work done. She said that the problem would not do damage to the motor. Only that I needed to be aware of the problem, and to be prepared in case the motor died while going to throttle (i.e. don't crank up and run across the river in front of a barge). She also suggested pumping the bulb prior to startup might help, and allowing the motor to idle for a few minutes prior to throttling up may help too.

It will probably be a while before I have the service done, but if I can remember to (which I seriously doubt), I will post the results on this thread. 2ndTry, if you have the work done, please keep us posted. Thx.

 

[2ndtry]

Re: Gas issues at high temperature

Thanks Big River, good to know. Also good to know my dealer is not an "experienced service center", they charged me $90.00 to change the anti-siphon valve (this did not fix the problem).

I'll give them a call tomorrow.

 

[jgso]

Re: Gas issues at high temperature

I have the same problem and understand that zuki customer support is aware of the problem and has a fix. I believe the problem is vapor lock. The engine is an'05 DF140 Anyone have the service bulletin for the issue and fix? Or anyone had the problem and knows what the specific fix is? My dealer can't fix and is unaware of any zuki service bulletin regarding the issue.