Ok Merc issues

[bigshrimpin]

MJ - I think it's bogging cause it's not getting the fuel it needs at higher RPM (above 4500). Whether it's the fuel pump, carbs, or some restriction b/w the tank or motor . . . We'll have plenty of time to go through the entire system this winter and replace/rebuild everything. Those motors run HOT at lower speeds, you can add a H20 pressure gauge and a temp gauge to ease you mind. I run snipped tstats during the warm months, so the motor runs colder and pees right away . . . but you can flood the motor when starting (as I showed you almost everytime we went out) Hopefully Spares or Ferm will come along and chime in here.

[chumbucket]

Originally Posted by bigshrimpin

MJ - I think it's bogging cause it's not getting the fuel it needs at higher RPM (above 4500). Whether it's the fuel pump, carbs, or some restriction b/w the tank or motor . . .

That's pretty much what I was saying. At speed I felt the primer bulb and it seemed to me that when the motor bogged, the bulb went a bit soft. Then it filled and hardened again. The only doubt I had was that it didn't seem to make a difference whether I squeezed the bulb or not. The motor would still quickly drop RPMs, then pick right up again.

[bigshrimpin]

MJ - Don't forget to remove that saltwater sprinkler system showering the motor while underway :)

[THEFERMANATOR]

My MERC ran just shy of 165 while trolling. At 2800 RPM's the temps would drop way down, but from 1000-2800 she ran about 160 and idle would run 145-155. Loopers need to run on the hot side at low RPM's to keep them from fouling plugs and burn the fuel. First thing is to take your filter off and drain it into a can or something and see what's in it. Also drain the float bowls on the carbs to see if some water made it into them. Did anybody try pumping the primer bulb when it would bog down? What kind of pump does that MERC have? The early MERCS had a big funky looking pump that would often fail, the later square ones are said to be ALOT more reliable.

[spareparts]

if it didn't make any difference when you squezed the bulb, then push the key in to chole the motor, if it picks up, you have a fuel issue between the fuel line and the intake, if it bogs down when you push in the key switch, it sounds electrical

[macojoe]

So the heat issue is normal, ok I just wanted to make sure!!

Therm, I planed on doing the filter and bowls, I am also going to replace the filter. The fuel pump is big and weird shaped so it must be the old one as you say??

Thanks spare thats easy ton do, thanks when I get it in the water thats just what I will do, if and when it bogs down again.

Ok Bs hurry up over!!

Thanks guys!!

[phatdaddy]

MJ. second what ferm said, my merc runs 15 to 20 degrees hotter when between 1500 & 2500 rpms. they really don't seem to like trolling. I'm assuming you taken the oil injection system off, if not , that might be a prob. on hitting the choke, not sure if those carbs have a butterfly or a gas pump that pumps a shot of gas to the carb. might make a difference to what spare was checking

[THEFERMANATOR]

Old style MERCS used the actual choke butterfly's. If it is an enricher style with the fuel solonoid, then it won't work if fuel pressure isn't present.

[Steplift 72']

Originally Posted by bigshrimpin

MJ - I think it's bogging cause it's not getting the fuel it needs at higher RPM (above 4500). Whether it's the fuel pump, carbs, or some restriction b/w the tank or motor . . . We'll have plenty of time to go through the entire system this winter and replace/rebuild everything. Those motors run HOT at lower speeds, you can add a H20 pressure gauge and a temp gauge to ease you mind. I run snipped tstats during the warm months, so the motor runs colder and pees right away . . . but you can flood the motor when starting (as I showed you almost everytime we went out) Hopefully Spares or Ferm will come along and chime in here.

I vote for the restriction between tank and carb....along with a different winter gasoline formulation. The anti-siphon valve takes a couple ounces of pressure to open the spring.....The butane added in the fall up north, and the south in November causes vapor lock if you happen to have a anti-siphon valve with a slightly stiff spring. I've been there and got the T-shirt....boat would bog down past 4000 rpm and stall if you didn't quickly pull the throttle back. Figuring that one out wasn't cheap or quick.

[macojoe]

Thanks but all these issues have been worked out and it runs like new! Now if i can just get all the ice to melt i be fine!!