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Honda BFP 9.9 D trouble

Dschaffer

New member
Hey all,
I have a 2018 (maybe 19) Honda 9.9 powerthrust that is giving me problems. It starts up with no issue but water does not come out of the “tell” unless I rev it a bit. Is it idling too low to engage the impeller? Is there a way to adjust the idle? It stalls out sometimes too if just idling.
A little history on the water pump. Last spring when I went to fire it up for the season (northern Michigan), no water came out of the tell so I brought it to a shop. The guy said the impeller was total destroyed and he was a little worried that some of the pieces might have gotten into the cooling system. I ran it all season without issue although I always felt it didn’t have a very strong water stream at idle and it would occasionally stall out. I mostly use the motor for trolling so it almost always has a “load” on it and performs just fine.
Another detail is that when I checked the gear oil before winter it had a little water in it. It was a very small amount of milky color but I drained it all out so it wouldn’t freeze. Is seems strange to me that this new of a motor would already be having these kinds of issues. Could water get into the lower end from the impeller housing area?
A little more detail to add. sometimes when I start it, the water comes out within a few seconds, but then once it gets to its idle speed, the water stops. Before its stops and its just a trickle, the water is SUPER hot. If I rev it a little, the water will come out faster and cool off. I wonder if it is stalling at slow idle because it doesn’t want to overheat?
Any help on this is appreciated.
Thanks
 
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The water pump is designed to pump water at slowest idle.----Strange that this motor has water pump issues,----Are you 100% sure the impeller was not run dry ?-----Still lots of folks out there that do not understand operation of outboard cooling systems !!
 
Those pissers are easily blocked by about anything. If you have access to compressed air, a couple of quick blasts will usually clear them. Lacking compressed air, back flushing with water may be worth a try too.

On the lower unit oil, nice catch! You might want to pull the prop to see if the prop shaft has a bunch of fishing line wound up on it. If so, that can take a seal out pretty quickly.
 
The water pump is designed to pump water at slowest idle.----Strange that this motor has water pump issues,----Are you 100% sure the impeller was not run dry ?-----Still lots of folks out there that do not understand operation of outboard cooling systems !!
If it was run dry, it was without my knowing.

Those pissers are easily blocked by about anything. If you have access to compressed air, a couple of quick blasts will usually clear them. Lacking compressed air, back flushing with water may be worth a try too.

On the lower unit oil, nice catch! You might want to pull the prop to see if the prop shaft has a bunch of fishing line wound up on it. If so, that can take a seal out pretty quickly.

I took the hose off and blew air through the hose. It sounds like maybe I should blow air back through the impeller? Would a partial clog give these symptoms?
I bought a new impeller, housing and gasket so if I don’t get a steady stream at very low idle it sounds like I need to dig into it, correct?
Is there any way to adjust the idle on these?
Thanks
 
It's worth check near the outlet, but I usually find the problem further in. Then again I'm generally working on older motors too....

If you blow air back toward the the impeller, then replace the pump, I'll be pretty surprised if it's not peeing pretty strong when you're done.

Yes, I'm sure there's an idle speed adjustment, but you'll need to work with somebody else on that. Not familiar enough with the little guys to be of much use giving you a hand there. I generally work on just the 40-90 hp stuff, HATE passing bad info....
 
First, take a close look at how the tell tale hose is routed. It should come from the fitting on the side of the engine block, UP through a hole in the splash plate and out to the side cover nozzle.
Those little hoses get mis-routed all the time and get crushed between the edge of the splash plate and side cover if not routed up through it's hole in the plate. I'm telling you this so that you don't make that mistake after trying what I suggest next.

Take the side cover off, take the tube off the nipple fitting in the side of the engine block and remove the fitting from the block. Then, start and run the engine in a trashcan or bucket of water. If there is debris in the tell tale passage it will come out if the pump is good. Water should GUSH out from the side of the block when the fitting is out. It should gush at idle but rev it up a bit to clear any debris. This is the MOST effective way to clear that passage.

If it won't gush at idle, the pump is likely weak OR there is a chunk of old impeller stuck at the tell tale bypass entrance. Try the compressed air with a rubber tipped nozzle in the hole for the tell tale fitting. If that clears it, you will still need to remove the gearcase and find the pieces since they could still come back up and plug the passages.

Since you've gone to the trouble of removing the gearcase, leave the tell tale fitting out and replace the pump. Then repeat running it again. When water will gush from the block at idle, replace the fitting and tell tale hose paying attention to the routing. You will know you have the hose routed correctly when it's a pain in the rear to hook the hose to the side cover fitting. If it's easy to hook up, you forgot to route it up through the splash plate hole.

Yes, you can adjust the idle. On the side of the carb nearest the engine block there is a slotted screw head with a spring under it. Turn it clockwise a little to increase idle speed.

Good luck.
 
First, take a close look at how the tell tale hose is routed. It should come from the fitting on the side of the engine block, UP through a hole in the splash plate and out to the side cover nozzle.
Those little hoses get mis-routed all the time and get crushed between the edge of the splash plate and side cover if not routed up through it's hole in the plate. I'm telling you this so that you don't make that mistake after trying what I suggest next.

Take the side cover off, take the tube off the nipple fitting in the side of the engine block and remove the fitting from the block. Then, start and run the engine in a trashcan or bucket of water. If there is debris in the tell tale passage it will come out if the pump is good. Water should GUSH out from the side of the block when the fitting is out. It should gush at idle but rev it up a bit to clear any debris. This is the MOST effective way to clear that passage.

If it won't gush at idle, the pump is likely weak OR there is a chunk of old impeller stuck at the tell tale bypass entrance. Try the compressed air with a rubber tipped nozzle in the hole for the tell tale fitting. If that clears it, you will still need to remove the gearcase and find the pieces since they could still come back up and plug the passages.

Since you've gone to the trouble of removing the gearcase, leave the tell tale fitting out and replace the pump. Then repeat running it again. When water will gush from the block at idle, replace the fitting and tell tale hose paying attention to the routing. You will know you have the hose routed correctly when it's a pain in the rear to hook the hose to the side cover fitting. If it's easy to hook up, you forgot to route it up through the splash plate hole.

Yes, you can adjust the idle. On the side of the carb nearest the engine block there is a slotted screw head with a spring under it. Turn it clockwise a little to increase idle speed.

Good luck.

Thank you for taking the time to give so much detail. I had checked the hose and it was routed correctly. I then removed the side cover and hose, yet still no water at low idle. I never removed the fitting the hose connects to so I will try that and the rest of the steps you have suggested later today. I’ll be sure to report back. Thanks again.
 
I pulled the lower unit and found that one of the impeller fins was broken off. The housing and metal plate were damaged too. I think what happed is that when I brought it to the shop last year they only replaced the impeller and not the damaged housing or plate. I had bought a new housing, gasket and impeller in case it needed all that so I was prepared but unfortunately, they sold me the wrong size impeller! Completely ridiculous. The only Honda outboard dealer in the area and every experience I’ve had with them has been bad. No more shops for me. I like supporting local and try to buy from the store whenever possible but this is ridiculous. Thanks again for all the help. Hopefully they get me the correct impeller tomorrow and all will be well.
 
I hate dealers, especially dealers with seasonal help. Yes, sure there's some good ones, but for everyone of those there's 5-10 more that are not to be trusted....

Any more, it's WAY too easy to look up your own parts and have them delivered to your door...

When they tell you that they can have the part in a couple of days, mention the fact that you can too.....
 
Sadly, it's a story we "hear" much too often on this forum.

Honda has a real problem with their "customer support" in my opinion.

I did contract maintenance for an "authorized Honda dealer"

Yeah, right!

They were "authorized" because they purchased enough outboards and parts. They didn't have a "resident" mechanic or parts person. They didn't even sell outboards! They simply spent enough dough with Honda and got the authorized shingle.

It really shouldn't be like that but it has been going on for YEARS!

You seem to be handy and confident and can do your own repairs. But, the people that aren't as well equipped are just left to the not so merciful hacks in your area.

A CRYING SHAME.
 
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