Sticky valves

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diamondback0320
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Sticky valves

Postby diamondback0320 » Wed Jan 17, 2018 3:44 pm

Anyone have any tricks on freeing up sticky valves?

SWAMPHUNTER45
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Re: Sticky valves

Postby SWAMPHUNTER45 » Wed Jan 17, 2018 4:07 pm

Seafoam can help.

I have had a Toyota engine tapping up top and added Seafoam to the oil then used a small vacuum line to draw into the intake while the engine was running.

When I used the vacuum line procedure it got free up and the noise left.

If you do the vacuum line trick you have to be very careful and do it slow. Fluids do not compress and you can damage rings etc. if you flood the engine.

READ THE INSTRUCTIONS / WATCH YOU TUBE FOR TIPS

GMAC 76
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Re: Sticky valves

Postby GMAC 76 » Wed Jan 17, 2018 4:58 pm

I agree with swamphunter45....a good dose of seafoam in the gas will sure help....it is a great old school upper cyl lubricant

Scarecrow
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Re: Sticky valves

Postby Scarecrow » Wed Jan 17, 2018 6:43 pm

Run some Marvel Mystery Oil in the gas and oil.

diamondback0320
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Re: Sticky valves

Postby diamondback0320 » Wed Jan 17, 2018 7:03 pm

Yeah I was thinking about running the marvel..never have used seafoam b4..

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Deano
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Re: Sticky valves

Postby Deano » Wed Jan 17, 2018 7:43 pm

Ya, I've always used MMO for such a purpose.
I got in that rut years before I heard of Seafoam.

Maybe I've been lucky but it's never failed to attain the desired result.
"The suppression of uncomfortable ideas may be common in religion and politics,
but it is not the path to knowledge; it has no place in the endeavor of science."
- Carl Sagan

SWAMPHUNTER45
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Re: Sticky valves

Postby SWAMPHUNTER45 » Wed Jan 17, 2018 7:48 pm

Marvel is cheaper!

I just have had better results with SF

diamondback0320
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Re: Sticky valves

Postby diamondback0320 » Wed Jan 17, 2018 8:28 pm

Not really getting much noise..boat idles fine & pretty smooth rmp up until bout 2k & the engine starts shaking & shuddering..new carb only has bout 10hrs on it if that..plugs we're looking good after replacing carb for a few trips out..the last trip hunting it was 30° & the boat didn't wanna run till I warmed it up for a few.. down the hill I went & across the lake..windy as hell to boot..boat was running decent until I got in the middle of the lake I I felt the loss of power & missing & backfiring thru the carb(I believe)..boat almost quit couple times in the middle of the nasty lake..3 days later coming home from camp boat run good for about 10min then same thing..when I came down to an idle & jump back up it wouldn't turn over 2500 & struggled to do that.. checked plugs & they were trashed..put new plugs in today & good run up till 2k & starts shaking..I do believe I have mag problems too but was told also sounds like sticky valves also

SWAMPHUNTER45
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Re: Sticky valves

Postby SWAMPHUNTER45 » Wed Jan 17, 2018 9:22 pm

I think a compression check would be a good starting point.

diamondback0320
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Re: Sticky valves

Postby diamondback0320 » Wed Jan 17, 2018 9:39 pm

Yeah gonna do that too..was just hoping maybe I could get the last weekend hunt in this weekend..idk tho

diamondback0320
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Re: Sticky valves

Postby diamondback0320 » Wed Jan 17, 2018 9:52 pm

All cylinder temps are 330-365°

GMAC 76
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Re: Sticky valves

Postby GMAC 76 » Wed Jan 17, 2018 10:00 pm

is there any chance the impulse spring on that Siamese mag has broken

diamondback0320
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Re: Sticky valves

Postby diamondback0320 » Wed Jan 17, 2018 10:06 pm

Greg it very well may be..I haven't heard it snap by turning over by hand in a long time..but it starts fine 90% of the time unless it's colder than hell

diamondback0320
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Re: Sticky valves

Postby diamondback0320 » Wed Jan 17, 2018 10:07 pm

I've got twister putting me a mag together as we speak.. should have that in a few days

Lwells
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Re: Sticky valves

Postby Lwells » Wed Jan 17, 2018 11:42 pm

If you do have a sticky valve then go with marvel mystery oil for I learned from an old military mechanic years ago that using it in with the oil and the gas will keep you from ever having a sticky valve. I had a Cessna airplane that constantly would stick a valve on a 6 cylinder continental and he told me to unstick the valve and put a quart of Marvel oil in the oil and a half quart in each wing tank for first couple fill ups and then to use a quart every time I changed the oil and to put a half quart in each tank occasionally when I fueled up and that I would never have another valve stick. Had my doubt but tried it . In the seven years I ran it after that I never had another valve stick so he made a believer out of me. As far as Sea Foam, I had a boat builder friend from Florida that swore by that stuff in boat engines. I've tried it in diesel pickups with good results on injector starting to stick or either the tips was getting clogged , don't know which but it straighted up after using it and running a few hundred miles. So it must be good also. That's my story and I'm sticking too it, unless I accidently drink a shot of one of these and then I don't guess I will be able to stick to my story.LOL

Alvinlee1915
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Re: Sticky valves

Postby Alvinlee1915 » Fri Jan 19, 2018 12:26 am

I'd go with what the people above me are saying.

Rich863
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Re: Sticky valves

Postby Rich863 » Fri Jan 19, 2018 10:27 pm

Sure it just wasn’t from being cold as hell? Did you try to lean it out any?
:old_glory: :florida:

diamondback0320
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Re: Sticky valves

Postby diamondback0320 » Sun Jan 21, 2018 6:49 pm

Yes tried leaning it out & no difference in it until the lean & rich cable was dang near closed off

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Re: Sticky valves

Postby AUK » Sat Mar 31, 2018 3:25 pm

Flow specs and testing done. 3/8 solid exhaust valve conversion in works. Parallel head.
Attachments
crankcasevent2.jpg
wet head
crank vent 3.jpg
wet head
20180225_224303.jpg
wet head
20180225_183732.jpg
wet head
20180225_183704.jpg
wet head

AUK
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Re: Sticky valves

Postby AUK » Sat Mar 31, 2018 4:14 pm

Picture in previous post of crankcase vent at tail pipe show egr type check valve that has been removed due to high cracking pressure, it was designed to be run after a pump it restricts vacuum. gauge in picture indicates crankcase vacuum in inches H2o.
Attachments
crankcasevent2.jpg
crank vent 3.jpg

AUK
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Re: Sticky valves

Postby AUK » Sat Mar 31, 2018 4:40 pm

Here is link to Lycoming exhaust valve, and guide issues. I have tested the oil flow or lack of to these heads on engines running mushroom lifters, the average flow to the heads is about .7 oz. per minute with 15-40 oil at 160 degree temp. at 80 psi. add that to sodium valve sending combustion heat up the guide and you get coking, sticking, wear. remember this is boxer engine no oil pooling on head. nothing to cool sodium valve roasted guide. dump some oil down that pushrod tube. Must have no pressure in crankcase to impede lubrication system. Lycoming will not publish crankcase pressures but Continental does in there overhaul manual. Lycoming has been laughing all the way to bank for decades.

AUK
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Re: Sticky valves

Postby AUK » Sat Mar 31, 2018 5:51 pm

Here is some info on Lycoming valve issues I will try to post document could not get link on search on Precision Engines Lycoming valve guide wear Bill Marvel, should get you something.
Attachments
The Rest of the Story- Valve Lifters and Tappets.pdf
Lycoming exhaust valve
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