How often do you adjust your tappets?

[geem]

EEERR - if the valve seats wear, the clearance REDUCES. The tapered valve is pulling through the tapered seat. Wear on rockers, pushrods and cams MAY compensate, but unlikely.

Loose valve clearances rarely cause issues. Tight ones do.......................................................

I said that in #11

 

[geem]

Don’t worry about tappet rattle so much. That’s not a cue for a need to check and anyway a bit of rattle doesn’t break the engine. When it sounds fine and your clearances are gone, the next step is a new head or worse. Some engines shrink clearances, some increase them. Best to check to schedule. My motorbike engine asks for checks at 12,000 miles, so in boat equivalent at 300 hours and if you ignore it and if you are unlucky it’s a new engine. If raced, it’s much less than this even - every few races. Valves can stretch as well as seats wearing leaving valves open when they shouldn’t be and that does all kind of no good.

I didn't have any tappets rattle. The Perkins manual says check every 500 hrs. Mine hadn't been done ever. At 3200hrs I checked them. Some very minor adjustment needed.

 

[geem]

Just out of interest what model of engine and what is the clearance for inlet/outlet. Do you check when warm or cold.
Thanks

Perkins M92b 0.2mm inlet, 0.45mm exhaust. Cold

 

[Zing]

I didn't have any tappets rattle. The Perkins manual says check every 500 hrs. Mine hadn't been done ever. At 3200hrs I checked them. Some very minor adjustment needed.

I know you didn’t. That wasn’t my point.

 

[jamie N]

How frequently are any of us adjusting the tappets on our outboard motors? Most of us will quite dilligently change the oils, and lube the grease points, but (probably) neglect to check the tappets as the engine's "running great".
I realise that those of us with the smaller lighter/boats are more likely to put hours on these.
To adjust them on my Honda 2.3 isn't as simple as I'd imagined, as it requires the removal of the engine from the rest of the unit. I've also a Mercury 4hp, a Tohatsu by any other name, where the adjustment is as simple as simple can be, and writing this makes me ashamed that I've not done either of these, so they're now again on the "to do" list.

 

[AngusMcDoon]

How frequently are any of us adjusting the tappets on our outboard motors? Most of us will quite dilligently change the oils, and lube the grease points, but (probably) neglect to check the tappets as the engine's "running great".

When I had 10hp as the main engine I checked them every year as it was so simple and required no replacement gasket with a rubber seal on the rocker box cover. They never needed much adjustment. I did my Yamaha F2.5 once and no adjustment needed. I never did it again as it needs a new gasket every time. E-Lite now.

 

[geem]

When I had 10hp as the main engine I checked them every year as it was so simple and required no replacement gasket with a rubber seal on the rocker box cover. They never needed much adjustment. I did my Yamaha F2.5 once and no adjustment needed. I never did it again as it needs a new gasket every time. E-Lite now.

15hp Yamaha Enduro. New in 2016. Flogged to death. Never adjusted anything. 2 strokes

 

[Supertramp]

Never worried about tappets until you mentioned it.

Beta 60 and it is recommended every 1000 hours. But Beta Owners forum suggests they go much, much longer without needing adjustment. Sounds like different engine makes may vary a lot in how often its needed.

Will order a rocker gasket in case.....

 

[NBs]

My Cummins qsb 5,9 need first chek 5000 hours,, say owners manual.

 

[Blueboatman]

Never (Yanmar )
Unless you include old Brit Triumph engines in which case I would say iirc quite often. On the flip side the oil was almost self changing

 

[Dockhead]

Don’t worry about tappet rattle so much. That’s not a cue for a need to check and anyway a bit of rattle doesn’t break the engine. When it sounds fine and your clearances are gone, the next step is a new head or worse. Some engines shrink clearances, some increase them. Best to check to schedule. My motorbike engine asks for checks at 12,000 miles, so in boat equivalent at 300 hours and if you ignore it and if you are unlucky it’s a new engine. If raced, it’s much less than this even - every few races. Valves can stretch as well as seats wearing leaving valves open when they shouldn’t be and that does all kind of no good.

When I was a boy, back in the last century, my Father taught me -- "if you can hear the tappets, there's no danger to the valves."

It's when you can't hear them at all that you might start worrying. As valve seats wear, the valves recede into the head, and clearance is reduced. Eventually there's too little clearance to keep the valves sealed, and they will burn.

Valve job is a major PITA, especially if you have less than excellent access to the top of your engine.

 

[Dockhead]

Simca cars in the 1970s always had very noisy tappets compared to other cars.

So did BMC Type B engines.

 

[DownWest]

Simca cars in the 1970s always had very noisy tappets compared to other cars.

That kicked a memory. Tried on a friends rear engined job. No chance, and read about the problems a bit later. Around '88?