Tulip Valve

-- This equation: boating(time + experience)/new problems=a trip to iboats.com

Anyway to share an experience... Last year I had an over heating problem in direct relation to my exhaust manifolds being totally occluded with rust, as is the result of salt water on cast iron. Fixed that only after the over heating melted my tilt/trim lines.

Looks like the over heating may also resulted in a tuliped valve causing my motor to miss; diagnosed by a compression check. I can beat myself up over this or learn from experience.

Since the motor is a 4.3GS PBYC built in 1998 I think it's time to repower with a 4.3 GXI.

Re: Tulip Valve

I have the EXACT same engine and yesterday I discovered #3 valve has tuliped. I just acquired the boat 2 weeks ago. Head is currently at a engine shop. Thoughts on what the cause is for this specific engine? Thanks

Re: Tulip Valve

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Re: Tulip Valve

DrNo08 said:

I have the EXACT same engine and yesterday I discovered #3 valve has tuliped. I just acquired the boat 2 weeks ago. Head is currently at a engine shop. Thoughts on what the cause is for this specific engine? Thanks View attachment 106122

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Which one is valve number 3? Is it the one on the far right?
From what I was told the tulip problem is caused by the heads over heating in relation to the exhaust manifolds over heating. Because of the rust building up the sea water isn't able to flow as it's supposed to to keep things running cool. I'm sure your mechanic will look for the cause also by checking your manifolds and risers. There's an alternative to replacing them with OEM cast iron parts however. There is a company that makes stainless steel manifolds and risers for our motor and lots of other. You'll be pleasurably surprised to learn the over all cost is cheaper than the cast iron replacements too. You may PM me and I'll share that link.

Re: Tulip Valve

Typically, overheats do not tulip valves.
Lugging the engine (over propped), improper timing, improper fuel mixture, etc leads to tuliped valves.

Re: Tulip Valve

Don S said:

Typically, overheats do not tulip valves.
Lugging the engine (over propped), improper timing, improper fuel mixture, etc leads to tuliped valves.

Click to expand...

Ayuh,... Or a Lean condition caused by what's sold as gasoline nowadays....

Water in the fuel is becomin' My worst headache...

Detonation, from Whichever cause will smoke a motor into an Anchor in No time Flat.....

Re: Tulip Valve

Biergarden said:

Which one is valve number 3? Is it the one on the far right?

Click to expand...

Thanks for replying. The middle one is tuliped valve #3. kinda tough to see from the angle the picture was taken but its the one. Compression on all other cylinders was in the 149 - 153 range. FWIW, my boat, a 1999 Larson 186 LXI, was always a freshwater boat and not put in saltwater. At least thats what I was told. Was purchased in TN and stayed there.