maybe cam problem please help

[badbowtie]

Okay well today went back to the lake and worked on it I have spark and fuel when it will not start. I finally got a hold of the previous owner and he called a couple people he knows and they are telling him that the cam that is in it is the problem It has a mild street cam would that be the reson it will start when I pull it up the ramp 10 feet back it back in and it will not start also any ideas were to get a decent marine cam I Don't want to spend 150.00 dollars on a cam and lifters and it still do the same thing.

For more about the problem please read this thread
http://forums.iboats.com/showthread.php?t=198743

 

[Windykid]

Re: maybe cam problem please help

Have you poured fresh gas down the carb bore???

I believe your floats misadjusted could be the problem.

 

[John_S]

Re: maybe cam problem please help

I doubt a "mild" street cam would cause the starting problems you are seeing. You should get the cam specs to see if you need to change it to prevent it from sucking water back into the engine. The key spec will be the LSA (lobe seperation angle). Once you get the starting problem solved, you won't want to trash the engine.

 

[badbowtie]

Re: maybe cam problem please help

I tried to even spray starting fluid in the carb and still nothing.

 

[Windykid]

Re: maybe cam problem please help

Check the basics, spark, timing, Ground wires, voltage etc...

I dont think a cam would cause this.

A street car can do a wheely and run straight with no angle problems.

With muffs try and start motor then jack up front end of trailer and try and start.

 

[Cptkid570]

Re: maybe cam problem please help

When it won't start, have you pulled the plugs to see if they are wet?

I've read on here that if you use an auto (not truck) cam, then the valves don't close at the right time and water can come into your engine and that a marine cam operates it differently and prevents that from happening...maybe your current cam is allowing water to come into your engine?? Just a theory..

 

[badbowtie]

Re: maybe cam problem please help

I am going to go back to the lake and I will pull a plug when in the water and see what it looks like. I checked all the grounds last night but I am going to check them all again and make I didn't miss something.

 

[Windykid]

Re: maybe cam problem please help

The cam valve lobe theory sounds good but isnt that what the exhaust flappers are for?

 

[John_S]

Re: maybe cam problem please help

My understanding of the flappers is that it helps prevents the backwash, like when you quickly come off plane, from traveling up the exhaust. Also, wakes and waves that hit the stern of the boat. The flappers do not completely seal off the water. Suction would be able to draw water past them.

If the engine started and died while the boat was floating, I'd suspect the cam more. But, cranking and just not starting? Also, wouldn't think the plugs would dry out as soon as boat was pulled up ramp. It is easy check to pull plugs and spin the motor to check if there is water in cyl.

What other changes have been done that went with this "mild" street cam? Says he has fuel and spark, very weird.

 

[badbowtie]

Re: maybe cam problem please help

I was told it just had a mild cam and was bored 30 over to freshin it up.

 

[whywhyzed]

Re: maybe cam problem please help

Most mild cams and marine cams have very similar grinds. Many are sold as "Marine/R.V." cams with the same grind as a mild perf. cam

 

[paulrfrancisco]

Re: maybe cam problem please help

Ive read all the posts from both threads and wonder if it could be a broken wire for the trim/trailer sensors that are shorting the ignition some how.. it seems that only when it is in the water it is a problem... I'll be there is no spark when its imersed.

If this moter was rebuild, then maybe the wrong wires were connected to the wrong connections...

 

[paulrfrancisco]

Re: maybe cam problem please help

Ive read all the posts from both threads and wonder if it could be a broken wire for the trim/trailer sensors that are shorting the ignition some how.. it seems that only when it is in the water it is a problem... I'll be there is no spark when its imersed.

If this moter was rebuild, then maybe the wrong wires were connected to the wrong connections...

Check for broken or frayed wired on the side of the gimble assembly.

 

[badbowtie]

Re: maybe cam problem please help

the trim gauge does not work right know I was trying to get the boat running then address that issue I know were both sensors are one on each side of the housing. Is their a way I can just unplug both of them and try the boat with them not even hooked up to see if that fixes it. I am heading to the lake tonight to check for spark again and see what I can find if their is a way to buypass them. please let me know So I can try that.

 

[SuperNova]

Re: maybe cam problem please help

If it is a cam problem it is more likely that the cam timing is off by a tooth than the cam grind. I've run mild to wild cams in outdrive equipped boats without any starting problems.
--
Stan

 

[Coors]

Re: maybe cam problem please help

He said he had spark and gas while on the water, so trim probably not it. And it runs on the trailer, off one tooth wouldn't change in the water; this is a brain-hurter.

 

[badbowtie]

Re: maybe cam problem please help

I had someone else checking spark that was just on the dock didn't seem like he even no what he was doing I should of had him crank so I could checked. So I am going back tonight to make sure I am checking myself I know I am getting fuel I have checked that myself If I am not getting spark is thier a way I can bypass the trim sensors. Maybe when they are under water is were they are screwing up. I am leaving in about 1.5 hours please keep feeding me Ideas to try So I can try a bunch of things tonight. The more and more I keep thinking, I bet I am not getting spark while in the water it don't even sound like it wants to start. I even spayed starting fluid and nothing it should of ignited on that fure sure.

 

[badbowtie]

Re: maybe cam problem please help

Okay well just got back from the lake again I have tested for spark it does have spark while in the water when it will not start. So I tried to pull the number one plug to see If I had water in the heads. I put my finger down buy the hole and had someone crank it no water came out but the boat started with seven plugs started right up. put the plug back in and what do you you know the boat started again. let it run for a minute and shut it off. Would not restart pulled just the wire this time and nothing just cranked. So I removed the plug again fired right up reinstalled the plug and it started again. Let it run for about five minutes shut it off and shur enough would not restart. I am just so confused why it is like this any more help would be great I am trying to go out this weekend and maybe get out on the lake. Thanks

 

[Coors]

Re: maybe cam problem please help

Having to remove a plug to start is abnormal. Maybe a bad connection; pull and clean and grease every connection you can find- use a wiring diagram so as not to miss any.

 

[badbowtie]

Re: maybe cam problem please help

Any links to were I can get a decent printable wiring diagram that I can print. That just seems weird that it will start on 7 reinstall the 8th one and it will start but only one.