Forcepower
Recruit
- Joined
- Oct 1, 2020
- Messages
- 4
Hi all new to the site recently purchased a 88 17’ Bayliner Capri With a 85hp for engine. First boat in great shape just trying to get the engine to run like a top. When I inspected the boat I did a compression test and all three cyl were at 130psi. I got the boat ready for the lake put new plugs in the engine which are ngk buhx. I added a see thru fuel filter before the fuel pump checked the fuel pump inlet screen which had alittle bit of debris in it but not a lot. Filled the tank with 50:1 premix using Lucas marine 2stroke oil.
Once Out to lake boat starts right up idles great,runs good from idle to about 2k rpms. Once I put to wot the engine rpms starts to climb Then Boggs down and the engine sputters. Tried doing hole shots to see if I could figure out what’s going on. The motor sounds good throughout until about 2500-3000 then starts sputtering. Tried hitting the electric choke and the motor wanted to die but didn’t. Trying to squeeze the primer build didn’t change anything.
I had the wife drive the boat while I was farting around with the engine. While she had it at wot and the engine is sputtering I manually shut the choke blades and the engine woke up and started to sing. Tells me the carbs are starving for fuel. I tried the primer bulb and it didn’t seem to do anything.
I tried looking through the basics on the ignition side. I noticed when replacing the plugs that the metal clip inside the spark boot for #1 cyl was rusty. Other two cylinder the clip looked new no rust. I tried cleaning and put dielectric on all the plug ends.
So after finding the problem with the choke making the engine run better I thought for sure the carbs were gummed up. I didn’t know what the PO had done so I pulled the carbs. I looks at the reed plates and they looked to be in good shape. I purchased new Boyesen reeds just haven’t replaced yet till I get the motor running right stock then I’ll change the reeds out. Pulling the carbs apart was disappointing because they were clean as a whistle. Not one spec of debris, float are level, plungers look new. The only thing I found that doesn’t seem right is the top carb has a #58 main jet and the other two have a #74 main jet. From my research they should all have a #74 am I right on this. Why would the top carb have a smaller jet than the rest?? And at such a big variance almost 20 sizes lower??
i haven’t dug into the fuel pump to see condition but I’m gonna order a new diaphragm and valves. I already order new float plungers and gaskets but looking at mine their very new looking.
I am new to the outboard world but am a mechanic by trade and am very competent on repairs just haven’t figured out what could be my problem yet. Manually closing the choke and the engine running better tells me there’s something going on with fuel delivery does that sound correct? Anyone know what main jets should be in tillson carbs for a 85hp force? Any info or tips would be greatly appreciated thanks.
Once Out to lake boat starts right up idles great,runs good from idle to about 2k rpms. Once I put to wot the engine rpms starts to climb Then Boggs down and the engine sputters. Tried doing hole shots to see if I could figure out what’s going on. The motor sounds good throughout until about 2500-3000 then starts sputtering. Tried hitting the electric choke and the motor wanted to die but didn’t. Trying to squeeze the primer build didn’t change anything.
I had the wife drive the boat while I was farting around with the engine. While she had it at wot and the engine is sputtering I manually shut the choke blades and the engine woke up and started to sing. Tells me the carbs are starving for fuel. I tried the primer bulb and it didn’t seem to do anything.
I tried looking through the basics on the ignition side. I noticed when replacing the plugs that the metal clip inside the spark boot for #1 cyl was rusty. Other two cylinder the clip looked new no rust. I tried cleaning and put dielectric on all the plug ends.
So after finding the problem with the choke making the engine run better I thought for sure the carbs were gummed up. I didn’t know what the PO had done so I pulled the carbs. I looks at the reed plates and they looked to be in good shape. I purchased new Boyesen reeds just haven’t replaced yet till I get the motor running right stock then I’ll change the reeds out. Pulling the carbs apart was disappointing because they were clean as a whistle. Not one spec of debris, float are level, plungers look new. The only thing I found that doesn’t seem right is the top carb has a #58 main jet and the other two have a #74 main jet. From my research they should all have a #74 am I right on this. Why would the top carb have a smaller jet than the rest?? And at such a big variance almost 20 sizes lower??
i haven’t dug into the fuel pump to see condition but I’m gonna order a new diaphragm and valves. I already order new float plungers and gaskets but looking at mine their very new looking.
I am new to the outboard world but am a mechanic by trade and am very competent on repairs just haven’t figured out what could be my problem yet. Manually closing the choke and the engine running better tells me there’s something going on with fuel delivery does that sound correct? Anyone know what main jets should be in tillson carbs for a 85hp force? Any info or tips would be greatly appreciated thanks.