Logo
FULL SITE MENU

15 hp popping and hard start

R

RCS

New member
Hello all-We have a 2007 15 hp BALJ 1401516. It has a hard start issue and it seems to have a "popping" noise coming back through the carburetor. Also on the side opposite the carb there is a plastic cover held on with two bolts and right above it there is a hole in the aluminum housing that water is dribbling out of. We had an unusual freeze here and I wonder if the engine froze and there may be a crack inside allowing water into one of the cylinders. I pulled the plugs and no rust or evidence of water was seen but I don't know for certain. The engine is sluggish revving up and idles poorly and stalls. A carb rebuild is probably needed but this water issue has me concerned. Does anyone have any insight or suggestions? Thanks to all.
 
Well, I can probably put your mind at ease about the freeze up. These engine's cooling systems dont retain any water. Almost all of the water drains out each time the engine is shut off.

I'm not sure what you are describing as far as where you see water dribbling but I suspect it may have something to do with the engine flush out port. Those flush ports are notorious for dribbling while the engine runs. The check valve inside can get a bit cocked to one side and not seal and, sometimes, mineral deposits on the valve and seat will keep it from sealing. You can buy a replacement valve and spring for just a few dollars at boats.net but most of the time you can take the valve out and clean it well enough to get it to seal up.

Popping back through the intake is typically caused by one of three different things.
1. Lean condition
2. Valve timing is off
3. Intake valve tight or hanging open

I agree with racerone that checking and/or adjusting the valves is a good idea. Especially if it hasn't been done before.

Checking the timing belt tension and timing marks is also indicated here. It is a basic, easy task on this engine. Honda timing belts are tough and these little twins rarely jump time but it does happen.

Carbon build up can cause these symptoms so if this engine idles or slow trolls alot then you may consider doing a decarbon procedure.

Many of the 15hp have something called a "fuel chamber" attached to the engine oil dipstick tube. It is a black, rubber cylinder about 1 1/2" diameter and 3" long. The fuel chamber can act as a water separator and fill with condensate. It's good practice to CAREFULLY remove it and shake out all the liquid inside every few months or anytime the engine is hard starting or doesn't run well. Be careful when removing and re-installing the chamber as it is fairly easy to snap the oil dipstick tube off if you use force. A little WD40 for lube helps make it slide on and off much easier.

Just a few ideas before carb removal. Although, yes, these carbs frequently need cleaning when not completely drained and allowed to sit. So, you may need to do that too.

Good luck.
 
[Open the fuel pump window in link below and the fuel chamber and it's "holster" are items 2 and 3


url]http
 
Last edited:
https://www.boats.net/catalog/honda/outboard-by-hp-serial-range

Sorry...struggling with my phone to send you links.

If you open the 15hp window and then "fuel pump"...you will see items 2 and 3 are the fuel chamber and it's holster.

If you open "thermostat" in the 15hp you will see items 2,3 and 4 are the flush valve components.

If you open the thermostat housing to work on the flush valve you might want to replace the stat and the housing cover seal since the stat is an every other season maintenance item. Pretty easy chore really.

Good luck
 
Last edited:
racerone said:
Does spark jump a gap of 5/16" ( 8mm ) or more , yes or no ?-----Have you checked valve clearance ?
Click to expand...
First-Thank you for helping me out. I do appreciate it! I did not verify a 8mm gap but I pulled the plugs and verified a hot blue spark on both plugs. Second,I have not checked the valves. I looked for a clearance setting and haven't found one yet. That could explain the popping noise back through the carb. I was just sitting last night and it came to my genius self it has a camshaft and valves and I know it's not been checked since it was new. (It's my Dad's motor} I will get that valve clearance checked as soon as I find the settings. Thank you so much!
 
jgmo said:
Well, I can probably put your mind at ease about the freeze up. These engine's cooling systems dont retain any water. Almost all of the water drains out each time the engine is shut off.

I'm not sure what you are describing as far as where you see water dribbling but I suspect it may have something to do with the engine flush out port. Those flush ports are notorious for dribbling while the engine runs. The check valve inside can get a bit cocked to one side and not seal and, sometimes, mineral deposits on the valve and seat will keep it from sealing. You can buy a replacement valve and spring for just a few dollars at boats.net but most of the time you can take the valve out and clean it well enough to get it to seal up.

Popping back through the intake is typically caused by one of three different things.
1. Lean condition
2. Valve timing is off
3. Intake valve tight or hanging open

I agree with racerone that checking and/or adjusting the valves is a good idea. Especially if it hasn't been done before.

Checking the timing belt tension and timing marks is also indicated here. It is a basic, easy task on this engine. Honda timing belts are tough and these little twins rarely jump time but it does happen.

Carbon build up can cause these symptoms so if this engine idles or slow trolls alot then you may consider doing a decarbon procedure.

Many of the 15hp have something called a "fuel chamber" attached to the engine oil dipstick tube. It is a black, rubber cylinder about 1 1/2" diameter and 3" long. The fuel chamber can act as a water separator and fill with condensate. It's good practice to CAREFULLY remove it and shake out all the liquid inside every few months or anytime the engine is hard starting or doesn't run well. Be careful when removing and re-installing the chamber as it is fairly easy to snap the oil dipstick tube off if you use force. A little WD40 for lube helps make it slide on and off much easier.

Just a few ideas before carb removal. Although, yes, these carbs frequently need cleaning when not completely drained and allowed to sit. So, you may need to do that too.

Good luck.
Click to expand...
First,Thank you for taking time to help. I will get the valves checked out as I know it hasn't been done. I will check and drain the fuel chamber thing also. This motor doesn't have a lot of run time but due to the age would it be a good idea to replace the timing belt due to age? I will try to post a picture of the water leak as well. Thanks for setting my mind at ease about the water draining out as well. I can mark frozen motor off my list. Thank you again-you guys are awesome!
 
jgmo said:
https://www.boats.net/catalog/honda/outboard-by-hp-serial-range

Sorry...struggling with my phone to send you links.

If you open the 15hp window and then "fuel pump"...you will see items 2 and 3 are the fuel chamber and it's holster.

If you open "thermostat" in the 15hp you will see items 2,3 and 4 are the flush valve components.

If you open the thermostat housing to work on the flush valve you might want to replace the stat and the housing cover seal since the stat is an every other season maintenance item. Pretty easy chore really.

Good luck
Click to expand...
Thanks so much for the help! I will get the items ordered that you mentioned.
 
Valve clearances are as follows:

Intake......0.15-0.19mm (0.006-0.007 in.)

Exhaust...0.21-0.25mm (0.008-0.010 in.)

The valves will get "tighter" as they wear into seats so setting them at least halfway toward the larger of the clearance should result in long term operation before any more adjustment is needed. If they already are about in the middle of the spec.then there's no need to adjust.

These specifications came from the Honda Marine Shop Manual for
BF15D • BF20D....fifth edition 2015.

Make sure you empty the fuel chamber and try it before tearing into any mechanical work. If you empty the liquid into a clear container and let it sit a few minutes you will be able to easily see if there is water present.

Hope this helps.
 
jgmo said:
Valve clearances are as follows:

Intake......0.15-0.19mm (0.006-0.007 in.)

Exhaust...0.21-0.25mm (0.008-0.010 in.)

The valves will get "tighter" as they wear into seats so setting them at least halfway toward the larger of the clearance should result in long term operation before any more adjustment is needed. If they already are about in the middle of the spec.then there's no need to adjust.

These specifications came from the Honda Marine Shop Manual for
BF15D • BF20D....fifth edition 2015.

Make sure you empty the fuel chamber and try it before tearing into any mechanical work. If you empty the liquid into a clear container and let it sit a few minutes you will be able to easily see if there is water present.

Hope this helps.
Click to expand...

Thank you for the information. I took a video of the water leak and I'll have to get it posted as well. Thanks again!
 
Here is where the water is dribbling from. The hole with the dirt in it above the plastic housing with two bolts. Thanks!
 
Last edited:
Back
Top