Another possibility...just checking...did you re-adjust your valve clearances after installing the new cam?

Ran it tonight with the brand new stock prop. No difference, really. 3200 rpms and 18 mph with a light load. Befoere I went to the lake, I double checked the air gap and key way. double checked fuel lines and tightened up hose clamps.

Oddly enough, the boat does not sound very loud like it normally does. It sounds as if it is running at about half throttle. Took it out of the water, started it up in neutral and it has that deep harley sound again and revs up to 4600 rpms......


Guess it might be about time to take it down to evt to have em open her up and see what is going on!

Where are you at in North Texas?

Let me know when you and Sanders get together and I would be glad to look at your engine and see if I can find anything.

Compression is good,new key,coils fireing ,boat set up appears ok. He does't say anthing that sounds like fuel proplems not sputtering or any thing

It started after the cam install, playing with different prop and boat muddied the water some. We know its not the prop (stock does not run), boat built by some one who does work for the mud market (Boat should be ok)

Its most likely cam timeing or cam lobes going flat. Put that motor on a boat that runs with a pro drive.
If it runs its the boat, if it does't open her up and pull the cam.

JD

I'm suspecting the cam lobes at this point too. If it is, I doubt evt will warranty it since I did the install.


Gary, The only thing I have done is sprayed WD 40 around the heads/valve covers while running to see if my gaskets were making a good seal. No change in idle when I did this.

I did say that the compression was good, but what I mean't was both sides were firing.

I really need to get a Briggs manual as I don't know how to do a leak down or compression check.

Don't bother with a leak down test. It will still push better than 32 rpm with all 4 valves leaking. You said compression was good. Ck it again. Warm up the motor ,pull both plugs, pull safety switch, wire tie the throttle all the way open. Make sure you have a good strong battery. Screw in compression gage spin to max compression, press the button on the side of the gage to release pressure . Repeat at least 3 times if its consistent , then do the other side. Stock should run 160 psi with no more than 10% difference between sides. My modded motor, push 210 + before break in. If one side is down put a 1/2 tea spoon of oil in Cly and see if it comes up.

I am betting cam timing or blown head gasket.

JD

Most of Brother's boats have a 15* transom angle. Mine does.

When i rounded my exhaust lobe on my 45 it did the same thing your saying, pull your covers turn the prop and see if the rockers are opening closing.................

UPDATE:

Went to check trot lines this morning and found that the throttle cable had stretched loose and was not getting full travel. Tightened it up and got 3950 rpms and 23.2 mph with me (210) and 9 gallons of gas. This is with a brand new stock prop. A step in the right direction but still not what it should be for a stage 1 with a cam.

The engine still wants to die when I put it in gear from neutral. Could this be from running too rich???

Have u tried to add a person to the boat? I can only get 27 if im by myself. This is because the front of my boat is full of crap like yours.

Try adding 200 lbs to the back of the boat and see what happens.

Also check the bottom of your boat with a sting level to make sure that it is not concaved or bowed from front to back and side to side.

good luck.....

are u blowing out your dipstick? I dont think ypu have a boat problem b/c my hull was beat to hell front o back side to side and was running 27 on the worst day.

Take that cam out and see what happens or wait a few more days and we can slap my motor on the back.

Did a compression check and it is 155 on both sides..... Talked to Mike at EVT and he said I should be closer to 180. He seems to think the cam is too agressive for just a stage 1 and I'm blowing all the compression back thru the exhuast. ( Sorry if I didn't explain that right, Mike.) Anyway, they are building the cams a little different now. Suppose to be good on the top end but does not sacrifice torque. I'm gonna send my stock one down there to have it reworked and see if that fixes my problem.

Well......... It does not appear to be a cam problem. I spent most of the weekend tearing her down and putting the stock cam back in. Went and ran with around 800 lbs and could only get 3250 rpms and 16 mph.

Since I know my compression is low, what else could it be if it aint the cam???????

Check your intake flange gaskets.

Whats the word man. Did you get the Drag Spec setup yet?

Working on it.... Ran it today and it ran pretty good. Got 26 mph at 4400 rpms with me (210) my boy (125) Trolling motor, 13 gallons of gas, 2 batteries, misc. gear in deep water.

The problem is that the accelerator pump is sticking open. Even with the new throttle set up. You rev it up and it wants to stay there instead of idling back down. It's a Mikuni issue but I don't know where to take it to get it looked at??????

any bike shop should know how to work on it.....

a harly shop will know for shore but the charge big bucks to look at stuff

GARY, YOU DA MAN!!!! I owe you a 12 pack, bud.

The bracket that holds the throttle cable was severly bent backwards. Straightened it out and problem is fixed! This has been the source of my problem all along.

I can't believe it was something so simple that has been giving me fits for nearly 2 months! It must have gotten bent when I took the motor off my old boat.

I little fine tweakin with main jet and prop and I will be set! Thanks again.

Glad you found it. You aren't the only one, its been a problem before- thats why I had a picture of it: