help my as is hard to start

[11.50fox]

ohh yeah sorry,  when I took my heads off today and flipped the over the number 3 cyc. the exhaust valve was super clean looking and the others were black/carbon looking. is that my burnt valve? cause my number 3 cyc. was 9.5 comp.just wandering. it really dosent look that bad just at a glance. I am taking the to machine shop tomorrow....

[RonT]

In that case go for it! Most calls I get are about increasing top speeds just to keep up with the neighbours boat, I tell them if you want to test an American SKier tie them pylon to whatever they have & play tug of war, sterndrives & outboards lose every-time.

[11.50fox]

what would be a good cam to get to match the heads and a dual plane intake??

[11.50fox]

heads are at the machine shop. valves were not burnt or bent. having the checked out and a valve job done on them now. what else could be my problem?

[Mike Harry]

Call Comp Cams and give them your info, check into one of their extreme marine cams........ Let them tell you how big you can go that way there is no mistakes.

There are quite a few variables, but they will help you out.

[shyskier]

is the combustion chamber & top of piston clean? if so had water leak into cyl. any sign of a leak at head gasket? if only exh. vale was clean I'm not sure what that could be. any sign of piston or cyl. wall damage? not normal from overheat unless piston burned & than you would have had a large misfire.

[11.50fox]

the exhaust valve was a lil cleaner that the others. but not like a burnt valve would look. the piston looked just like the other 7.

[11.50fox]

heads are back....not warped or anything.......... had to be a head gasket?

[phil]

In that case go for it! Most calls I get are about increasing top speeds just to keep up with the neighbours boat, I tell them if you want to test an American SKier tie them pylon to whatever they have & play tug of war, sterndrives & outboards lose every-time.

I always wondered if people have tried this..

[shyskier]

it would have to be a large head gasket leak to have 10 psi compression. only other thing i can think of would be a stuck open valve. you should have done a wet test on that cyl. before tear down ( sqirt oil into low cyl. & recheck comp. if comp. higher = ring fault). but I doubt worn or broken ring would cause that low reading.

[backfoot100]

Batteries:
2) Ski boats have dormant periods, 3-6 months of doing nothing. Batteries that are cycled regularly seem to live longer.
3) I have not seen a ski boat battery last more than 3 years, where my little parts truck is going on 6 years with the same battery type/size I use in my ski boat & it is going strong.

Agree Ron with the following caveats:
Move someplace where you can use it year round and you won't have that problem near as much or get an Optima Red Top.
I had a Red Top that I bought for the boat back in WI before I moved to FL. A couple years ago I started having some starter issues and I thought that the battery had lost some of it's cranking power (which can in turn weld starter relay contacts) so I replaced it with another Red Top.  After all, it was now 11 years old. The new Red Top I got online so I didn't have a core return. I had that old battery sitting on my garage floor (on a rubber pad) for over a year and never touched it.
The battery in my truck died and just for the hell of it, I measured the voltage on that old battery seeing as it was just collecting dust now. It looked good so I put it in my truck. Been in there for the last year working fine. It's now 13 years old and still works great. It does definitely loose it's charge pretty quick if you leave lights on or a door open, but it still works.

I know that Optima batteries aren't cheap but when they last 11 years in a boat, sit on the floor for a year, then spend a year in a truck still getting the job done, they're worth every penny.

[shyskier]

a batt. that is discharged will lose some of it cranking power & will not fully recover.  the best way to store a batt. is with an automatic charger/ maintainer to keep batt. fully charged.  I store my batteries in crawl space & charge every 2 - 3 mo. had a delco batt. that was a warranty return & used it for 8 years. high heat is also harder on batt. life than cold temps, but batt. will loose cranking power when cold.

[C0R3Y]

I too have a hot start issue with my 90’ 454. I did run it with a shotty impeller earlier in the season (water was >50 degrees), and ran it up to 270 degrees. However, according to my owner’s manual overheating isn’t an issue until 180 degrees.  The boat has been difficult to start since I bought it in November. I didn’t think much of it, just figured I had to get the “feel” of the boat. I am not used to carbureted marine engines. I always assumed that I have flooded it out and needed to let it rest, before attempting restart, because it has eventually turned over. I plan on doing a tune up (oil, plugs, and wires) before I get it wet again. Any other suggestions, I can do easily myself, that may help my issue? If this is a common problem what is the most common fix?  It’s seems to be near impossible to research issues for the 454.

-Corey

[RonT]

No problem with support here, yes 180 deg. is MAX, 270 tells me you had fire breathing down the exhaust tubes! Sounds like a total tune-up is in order plus some very careful cooling system inspections. Glad to help you when need it.

[C0R3Y]

My fault *270 degrees was a typo. It should of read *170 degrees.
After reading through a metric ton of threads on here, web searches, and talking with anyone who will listen, I think my problem may be vapor lock. It matches all the symptoms; solid cold start, fails to start hot, but after I have the hatch up poking around and not really doing anything it fires right up. I'll be back home next weekend to thoroughly troubleshoot the issue.