I have a 18GDLT. I bought it used and it doesn't have a rpm's gauge. the muffler glows red hot when I run it wide open. I called go devil and they said its normal. the said that motor should run about 15. I put it on the GPS and I am running 17 with two people. Stock prop. I think I might be running more rpms than I am supposed to be. What do you guys think?

What size boat do you have it on

It is on a 1548 Alweld.

I run 18 with two people on a 14 by 36 with brand new prop and a 20 hp. motor.

the title of this thread cracks me up.

Your getting good speeds, dont change anything, and dont expect to get any faster.

I dont think you guys are understanding what I am asking. I want to know, since I dont know how many rpms I am running if it is safe to just run my motor wide open. I believe this is an after market throttle. Is it ok to just open her up and let her run like that. I mean the muffler glows so red I could use it as an anchor light.

Buy a tiny tach to put on it. You could drastically reduce the life of your engine if you're over-revving all the time. Red hot like a light don't sound right, you could also be running very lean causing things to overheat. Get a tach first. What size prop you have on that rig?

Mine and every other long tail i have ever seen glows red, my buddies surface drive has a blue flame about a foot long shoots out of his pipes.

Can someone post a link to one of the tachs being recommended, I beleive thats my next purchase. And post what RPM's a 25hp Kohler should max out at. And is it a simple adjustment on the high end stop where the throttle cable bolts up to the carb? Thanks - John