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BF50D Fuel pump issue

Update on the HP pump issue. First a huge thanks to avh for laying out for me the procedure to access the HP pump. I followed the instructions and managed it ok. Also a thanks to iang6766 who made me aware of the possible other issues. I took a pragmatic approach and first changed oil and filter + spark plugs. No change still cutting out after 15/20 mins. Then changed thermostat, No change. Replaced the injectors, No change. Replaced HP fuel filter, No Change. Replaced LP fuel screen, No change. So I was left with tackling the VST and this Grommet, Well today thanks to the contributions from this forum I stripped the VST out and found the offending Grommet. There it was bottomed out, clearly showing indentation on the end of the grommet. So cut the first section away and refitted everything and heypresto the motor ran great with no cut out after 15/20 minutes, so ran for a further 30. No problems apparent. Really surprised that Honda produced a motor with this built in fault, it rather knocks the reliability reputation. Hope that this will help others who have the same symptom's. Its daunting at first but when taken step by step it can be done.
 
I have this issue with my 2014 Tohatsu 90 which is just a black Honda. I recently replaced the grommet (actually named insulator) and still have the problem but it is harder to make it fail. Now it doesn’t stall but if I shut it off after a long idle and let it sit for 5 minutes, it won’t start. It did start after sitting another 10 -15 minutes. Previously it would take 45 min to an hour.

I did not trim the grommet before I installed it. Also I installed the grommet on the motor before reassembling the VST. Someone mentioned installing the grommet into the housing rather than on the motor. I don’t think it should matter.

Is there a downside to trimming this part? Since I just put a new grommet in I don’t like the idea of trimming it. Does anyone have pictures of how you trimmed it? Does it have to seal on that edge or can you just cut it off with a utility knife? How does Honda recommend fixing this?
 
Makes no difference whether you trim it or not. Have you checked your fuel cooler is clear and that hoses to it aren't blocked. Sounds very much like vapour lock.
 
Makes no difference whether you trim it or not. Have you checked your fuel cooler is clear and that hoses to it aren't blocked. Sounds very much like vapour lock.
I agree, it looks a lot like a vapor lock. There are no blockages and the VST is clean. I’m stumped.
 
I’ve read thru everyone’s comments here some of you have given super responses. I have a Honda 50hp efi with same issue. I have checked everything bringing fuel to motor all good. Primer bulb stays hard also. Boat shop just did filters no change. So it looks like I’m gonna tackle the grommet for lack of any other issues I can find. Wish me luck. Any advice before I tackle?
 
I’d like to thank everyone on here. I took apart my engine yesterday and found the grommet exactly as was stated, trimmed it carefully with a razor blade and reassembled. Tested today on water and it ran flawless. Ended up using for several hours without a single issue.
 
After replacing the grommet and flushing out the cooling system I’ve almost eliminated the problem. Now if I run it for a while followed by a long idle and shut it off for 3 to 5 minutes it is hard to start. After waiting another 5 mins it starts just fine. I suspect the problem will return as the grommet swells slightly. This is the worst time of year for this problem as the heat index is over 100 and the water temp is in the high 80s.
 
I agree, it looks a lot like a vapor lock. There are no blockages and the VST is clean. I’m stumped.
I tried flushing the engine with the hose connection instead of running it with muffs. It’s seems better as I was unable to make it fail when I took it out. I usually don’t flush it if I am in fresh water and just back it down the freshwater ramp and run it after going in salt. The hose produces more pressure than the engine does at idle but probably not as much as at WOT. If it gives me any more trouble I’ll try cutting down the grommet.
 
Hey guys I have read thru this thread from start to finish and I'm considering doing the grommet trim fix to my 2016 BF60A. I just got the engine this summer and it ran great but after shutting it off and trying to restart it takes a few tries. This has happened twice to me now. I bought new fuel filters (both) and plan to change those first, but while I'm in there do you think it would be worth it to do the grommet fix at the same time?
 
Hey guys I have read thru this thread from start to finish and I'm considering doing the grommet trim fix to my 2016 BF60A. I just got the engine this summer and it ran great but after shutting it off and trying to restart it takes a few tries. This has happened twice to me now. I bought new fuel filters (both) and plan to change those first, but while I'm in there do you think it would be worth it to do the grommet fix at the same time?
I have heard that Honda has a service bulletin about this but have not been able to see what it says. If the grommet could be 3 or 4 mm shorter, and still function properly, that Honda would have changed it. Perhaps they have a batch that were made from the wrong material. I installed a new grommet (Honda calls it an insulator) and the issue may be resolved. Unfortunately due to family issues I have not been able to test it as thoroughly as I would like and there has not been enough time pass for the grommet to finish swelling.
It’s unlikely that your filter change will fix your issue but it may make it more manageable. I’m looking for direction from Honda, Tohatsu or a certified mechanic before I trim mine.
 
Thanks, I changed the low and high pressure filters this weekend, the high pressure filter looked really dirty. I'll test it out this week and see if that fixed the situation. My issue wasn't as bad as others posting on here so I figure I might get away with just a filter swap and be good.
If not I'll dig into it this winter when theres time.
 
Thanks, I changed the low and high pressure filters this weekend, the high pressure filter looked really dirty. I'll test it out this week and see if that fixed the situation. My issue wasn't as bad as others posting on here so I figure I might get away with just a filter swap and be good.
If not I'll dig into it this winter when theres time.
If your HP filter is really dirty, I strongly recommend that you pull the VST apart and check it for contamination. Also check the HP fuel pump for rust. There are good YouTube videos on how to do this.
 
If your HP filter is really dirty, I strongly recommend that you pull the VST apart and check it for contamination. Also check the HP fuel pump for rust. There are good YouTube videos on how to do this.
Thanks, I'll look into this now that summer is about over here. I've looked on youtube for this but havn't really found a decent video, I feel dumb for asking but do you have a link to a good honda VST video? I have a honda service manual now, I'll do the fuel insulator grommet fix also when I'm in there.
 
Hey guys I have to thank you all for the info on the fuel pump grommet. I just finished doing the work on my 60 and I made a youtube video of the steps I took. The video is twice as long as it should be but about half way thru you can see the old grommet and the new one I replaced it with. I have not had a chance to test it on the water but I'm certain that was my hot start issue. Here is a link to the youtube video I made.

 
I never did trim the grommet/insulator. I had the boat out yesterday and had trouble starting it after extended idling. The grommet/insulator on mine is sealed off at the end facing away from the motor. If I trim it there will be a hole through it.

Does anyone know what this part does? Honda calls it an insulator so I’m assuming it is a heat insulator vs electrical. Does it slow the conduction of heat from the motor to the fuel? As I said back in the thread, mine is a 90 but I think it’s the same part number that Jermbos used.
 
Hey guys I have to thank you all for the info on the fuel pump grommet. I just finished doing the work on my 60 and I made a youtube video of the steps I took. The video is twice as long as it should be but about half way thru you can see the old grommet and the new one I replaced it with. I have not had a chance to test it on the water but I'm certain that was my hot start issue. Here is a link to the youtube video I made.

Oops, I was wrong. It’s exactly like Jermbos. I think I will be trimming the grommet some time this week.
 
Oops, I was wrong. It’s exactly like Jermbos. I think I will be trimming the grommet some time this week.
I would order a new one from Honda if you can, the reason is that the old material swells and it'll keep swelling over time. The new replacement part is made of different material that shouldn't swell, and its also shorter in length.
 
It’s been a while since I posted on this problem. If I run my engine at high speed for 5 to 10 min and return to the dock at idle taking another 10 min, then turn off the engine and wait one min, it won’t start and I can’t hear the high pressure fuel pump run. If I let it sit for 30 min or so, it starts and runs normally until I do another long idle. The vst and hp pump are warm to the touch but not so much that I can’t keep my finger on them. Probably 130 to 140F.

I have flushed the cooling system with a 50/50 vinegar/water solution for 3 hrs, installed a new impeller and thermostats and inspected and cleaned as much of the cooling system that I can get to. In addition I trimmed the infamous grommet mentioned in this thread. Nothing has made any difference.

The only thing I can think of that I haven’t done is to change the hp fuel pump. I supposed I could also try getting the latest version of the grommet from Honda. Note that mine is a 2016 and the fuel outlet is aligned with the pump outlet port unlike the one in the pictures above.

Does anyone know what the grommet does? Honda calls it an insulator. Heat or sound? The fuel pump is cooled by gas so does the part somehow control the flow of fuel over the pump? It would seem that the diameter of this part would matter as much as the length. swelling from ethanol could make it a plug. I wish there was a good technical description of this system and how it works.

Any advice is welcome
 
Hello, I have the same problem. I’ve replaced the low-pressure pump, the fuel tank, the primer bulb, and checked the high-pressure pump — it holds 3 bar. I’ve also replaced all the filters, but after some time the engine dies. Sometimes it won’t start at all; I wait about ten minutes, and then it runs again until it dies once more. I also noticed that insulator, it looks fine, but I’ll trim it a bit and try again.
 
I would change the grommet to the new style, its a $10 part at the dealership. I had more issues after doing the grommet fix but it ended up being my fuel pump. So my theory is that the restricted grommet made the fuel pump work harder than necessary and it prematurely failed. Now I have a new fuel pump and grommet, I did test it once and all was good, but snow on the ground, so it is put away for the winter.. I'll report back in the summer if I Have any more issues.
 
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