1995 70 hp force

[barefootpoppy]

Anyone know if the carb and fuel pump on a 1995 70 hp force is the same as the carb and fuel pump on a 1998 75 hp force? They are both by mercury marine.

 

[JB]

Re: 1995 70 hp force

Howdy, poppy.

Welcome to iboats.

This is pretty specific Force stuff. Let's try the Force Forum. You ought to get better response there. I will move this for you.

Good luck.

 

[emoney]

Re: 1995 70 hp force

Different part numbers, that's for sure. Www (dot) boats (dot) net has the parts list and drawings for almost every outboard built, to include all the Force models back to the early 80s. They show two different carbs between these two motors. One of the smart guys around here will weigh in I'm sure and be better able to answer what can be used, etc., but I thought I'd pass along that webpage as it's pretty handy, especially for us FOrce owners. If I was a guessing man, I'd be willing to say the fuel pumps will interchange though.

 

[jerryjerry05]

Re: 1995 70 hp force

Different carb #s
Different jets.

 

[roscoe]

Re: 1995 70 hp force

They us the same fuel pump.
Standard square Mercury fuel pump, used on Mercuries from about 1988 on, and on Force motors from 1992 on.

 

[barefootpoppy]

Re: 1995 70 hp force

Different carb #s
Different jets.

Thanks saw em on ebay thought I'd give it a try. I have a 1998 75 hp Force markings are 75 ELPT OE309635. I am losing power at WOT. Here's what I tried so far:

Checked spark all cylyders good
Tune up new plugs
Fresh gas new marine grade fuel lines from the tank to the carb
checked vent tube it's open
new primer bulb
rebuilt fuel pump and carb
checked compression all cylinders about 120 and good
didn't mess with timing as I'm by myself and should be done at WOT

Any ideas and or links to try next?

 

[barefootpoppy]

Re: 1995 70 hp force

also don't know if I included put in new fuel filter and water fuel seperator

 

[barefootpoppy]

Re: 1995 70 hp force

Also I have a built in fuel tank and tried a portable tank and it was the same way

 

[emoney]

Re: 1995 70 hp force

Be a little more specific in that, is it totally dying when you try to go WOT or does it bog down? Do you have a tach and know what RPM's you're reaching? When you rebuilt the fuel pump, did you change out the diaphragm? Is your carb giving you issues, is that why you're looking for a replacement?

 

[barefootpoppy]

Re: 1995 70 hp force

Be a little more specific in that, is it totally dying when you try to go WOT or does it bog down? Do you have a tach and know what RPM's you're reaching? When you rebuilt the fuel pump, did you change out the diaphragm? Is your carb giving you issues, is that why you're looking for a replacement?

at WOT it runs fine but loss about 8mph and seems to really be burning a lot of fuel. also big loss of power can't get her back up on the trailer without the winch. did a complete fuel pump rebuild including diaphragms and check valves and gaskets. suspected the carb after fuel pump didn't solve the problem. not sure of the rpms didn't make a mental note of that last time out.

 

[emoney]

Re: 1995 70 hp force

Are you sure the prop hasn't spun the hub? That year model had the "Flo-Torq" hub from Mercury which is a plastic sacrificial sleeve and it's designed to "take the fall" should you hit something or get something wrapped around your prop. Better than replacing the lower unit. If it's running fine through-out the RPM range, it may be time to at the very least, inspect the prop & lower unit. Does it get up on plane like it should or is it now taking longer? From where are you getting your speed #s the gauge or a GPS (GPS is only one you can rely on)? Have you noticed a sound difference in the motor, and was there a specific event that brought this all on?

 

[barefootpoppy]

Re: 1995 70 hp force

I'm not sure that the prop hasn't spun the hub. How do I check that? If I take off the plug wires and put the motor in gear then turn the prop it has compression and turns the motor over. It's taking longer to get up on plane. I used my gps for mph. I was going down the lake at wide open throttle running fine when there was a loss in power and the motor stalled out. It wouldn't start again. And I pumped the primer bulb and got it started but it was running ruff and stalled again. So I pimed it again with the primer bulb and it limped back to the dock. That was the first sign of problems. Now after all the previous steps that I've done it runs without stalling out but uses a lot more fuel and loss power at WOT and mph's with little hole shot.

 

[barefootpoppy]

Re: 1995 70 hp force

I did service the lower unit about a month ago. I replaced the water pump impeller and changed the gear oil. All was fine after that for many outings though. I didn't take the prop off though at that time.

 

[emoney]

Re: 1995 70 hp force

To check it you can take a grease pencil and mark a line from the center of the hub out to the far edge of the rim of the prop. If it's "spun", that line will be 'broken' when you check it again. If it's still intact, then you're good to go. Give Jerry or Frank or one of the other guys time to see your last post and they'll weigh in on other things to troubleshoot in the motor as well. When you say "with little hole shot" are you saying it's gotten worse or is the same when getting up on plane?

 

[barefootpoppy]

Re: 1995 70 hp force

so if I understand correctly I should take off the locking nut on the prop? mark the line. install the nut and run it. if the line is broken it's spun? is that right? also it has gotten worse when getting up on plane since this issue started. I have to trim it now where I didn't have to b4.

 

[barefootpoppy]

Re: 1995 70 hp force

that is I have to trim it to get it up on plane everytime I go wide open throttle where as b4 this issue once up on plane at wot I didn't have to trim it after the first time up on plane there is a definate loss of power now getting up on plane since this issue

 

[emoney]

Re: 1995 70 hp force

You might even be able to mark it without removing the nut, but yes, that's the idea. Pretty simple when you think about it, because if the 2 halves of that line are now separated after running it, there's obvious movement in the hub. That will cause symptoms that you've mentioned, but sadly it's not the only thing that could cause them either. I'm of the "rule out all possibilities" camp, especially before I start throwing money at a problem.