Honda Gold Wing, Sticking Valves, How much to fix?

I have a 1989 Gold Wing 1500 with 73,000 miles on it, on which one of
the engine valves is starting to stick.

When I start it up cold, it sometimes runs on 5 cylinders for a while,
then the sticking valve frees up and it runs fine after that.

I'm pretty sure it's a sticking valve because when running the starter
I can hear the starter surge when it goes past the cylinder with the
open valive.

In general how much should it cost (i.e. how many hours should it
take) to do a valve job on a 1500?

 

I doubt it, myself.

 

Before you do anything drastic like tear the engine down, I'd try a Marvel
Mystery Oil shock treatment. Sometimes works good to free up sticking rings
and valves. Might not help but certainly won't hurt.

 

Good afternoon, Ken.

I will try that.

What exactly is a "shock treatment"? Normal treatment is 2 oz per 5
gallons of gas or 1:4 ratio in the crankcase. Does a "shock"
treatment just use a higher does of MMO?

 

In addition to BOTH of the above.................
You put some directly into the cylinders (hot), thus:
(In a cage, you just pour about 8 oz. rapidly into the carb. at fast idle
until it dies.)
Warm engine.
Remove plugs.
Put about 1-2 oz. in each cylinder (depending on the size of your jugs!)
Put back plugs finger tight.
Turn over a couple of times but DO NOT START.
Let it sit (at least) overnight.
Tighten plugs (cleaning optional).
Fire it up and pray! (Expect some smoke and maybe a hard crank the first
rev. or two).

The only drawback with this is: going in through the plug pretty much misses
the intake valve guide(s).

Good luck!

 

Good evening, Ken.

Thanks for the info on the "shock" treatment.

I think I am not quite in a condition that will require that, yet.
But, we'll see.

I bought a 16-oz bottle and put about 3 oz in 5 gallons of gas and
poured the rest into the crankcase. Started it up and it ran nice and
smooth (but, it usually does that anyway... it's only occasionally
that I get a sticking valve, or whatever it is, and it runs rough for
the first minute or three).

Ran it a couple of miles at 60 mph and then put it away for the
upcoming thunderstorm :-(. Ran nice and smooth, if anything better
than it has in a while.

I'll have it out again tomorrow. We'll see how it goes.

I'm wondering if I should park it on the center stand rather than the
side stand, if it's going to be parked for a while (overnight or
longer). Someone said something about oil flowing into the lefthand
cylinders when it's parked on the sidestand ... wouldn't have any
effect on sticking valves, but sure would make it smoke for a short
time after startup (which mine sometimes does).

 

Like I said originally, I doubt that it is this. It's so rare nowadays,
and on a low-mileage Wing....

Ah. You're starting to see sense...

 

<TOG>>>>>Like I said originally, I doubt that it is this. It's so rare
nowadays, and on a low-mileage Wing....<<<<<

Good morning, Gent...

It has 73,000+ miles on it, all of them mine. I'd say that's probably
"mid-mileage" for an 18-year-old bike.

I always did, I think... I never said "It's definitely a valve", only
deduced that that's probably the most likely given all of the
symptoms.

The main symptom that points to a valve is that when the starter motor
is turning the engine, but before the engine fires, I get a sort of a
surge in starter speed as it pulls one of the pistons through the
compression stroke, sort of what you might expect to hear if you left
one of the spark plugs out.

When it does that, the engine runs rough for a minute or two, then
smooths out, Shut the engine down, run the starter again, and it
sounds normal.

If not a sticking valve, what else could that be?

 

OK, back to square 1.

I think this means that one cylinder is firing and one isn't.
Although it could be valves, that's probably the last thing I'd consider.

Ignition: How long since plugs were changed?
Plug wires & boots: Can arc in the morning when damp.
Fuel: Pilot jet on one side partially blocked or if FI one injector sticky
Choke or enricher not working right on one side.
Crack in boot between carb and engine (closes up when warm/hot)

If you have been parking on the side stand, there might be enough ring
leakage that it simply is a matter of momentary oil fouling of the "down
side" spark plug.

Good luck. I really don't think you are going to need a valve job.......at
least not from this "symptom".

 

Good morning, Ken.

The crankcase capacity of the GL-1500 is 3.7 US quarts. The MMO
bottle instructions say "One quart of Marvel Mystery Oil added to
crankcase oils...". To my knowledge most cars hold 4 quarts of oil, 5
if the filter is changed, so I think that the dose I gave it (13 oz,
or 3 oz short of a pint) is about half of the dose recommended on the
bottle.

My oil was a little over half a quart low when I started this exercise
so now it's just a shade under the full mark.

 

I would agree with you (and would never have considered a sticking
valve) except for ONE thing.

When you engage the starter on any piston engine, the sound you hear
(prior to the engine actually starting) is the starter turning and
getting loaded down (thus speed momentarily reduced) every time it
pulls a piston through the compression stroke.

Now imagine that somebody stole one of your spark plugs during the
night and you didn't notice. You hit the starter and hear the normal
starter motor sound UNTIL the cylinder with no spark plug gets its
piston pulled through its compression stroke. There is no
compression, nothing to resist the starter, so the starter momentarily
surges in speed (and sound) as it pulls that piston through.

This is what I'm hearing (occasionally, not often, just sometimes).

There are really only four things that can cause that... a spark plug
that's been removed, a bullet hole in the cylinder , some SERIOUSLY
worn rings, or a valve that's stuck open, badly worn / burned, or has
heavy deposits.

The plugs are all there, I'm pretty sure no one drilled a hole in my
engine, the rings seem OK as evidenced by not a lot of oil consumption
(if any), and anyway the problem is intermittent and any of those
things would cause the problem to be continuous.

The only remaining thing I can think of is a valve that occasionally
sticks open. ANYTHING else would cause that symptom to be present
continuously and not just occasionally.

What am I missing?

 

It still sounds like a hell of a lot of additive, compared with the
quantity of oil it's being put in. I really would change the oil, and
forget the snake oil claims.

 

It's not fuel injected, if it's a 1989 bike.

This is possible. Some BMW Ks suffer from the same problem sometimes,
for the same reason

Agree 100% - I'd do the simple stuff first like a plug swap, and then
an plug cap swap, and then an HT lead swap, and then, er, then I'd
scratch my head. But it isn't going to be a stuck valve. And pouring
snake oil, sorry, magical fluids into the fuel and the oil will only
waste time and money.

 

Not really. Re-read my previous post, re: intermittent

And if you know so much about it that you are SURE that a valve is the ONLY
thing it could be, why in hell are you asking here in the first place????

Adios.

 

First hand experience with several different types of engines (old) leads me
to believe otherwise.

It is, after all, kind of like penetrating oil and that works wonders on
stuck bolts (sometimes).

OTOH, I never use the stuff routinely in anything........just to loosen that
occasional stuck "nut".

 

I did. Nothing in your previous post could account for the loss of
compression in a cylinder.

I never said I was sure it's a valve, I only said that seems the most
likely cause given the action and sounds of the starter motor and the
intermittent nature of the problem.

And for the record, I never asked what the problem was, I only asked
what I could do about it. I got some very good advice here, which I
have followed and it seems to have fixed the problem. We'll see in
the next week or so whether the problem is really gone.

Ken, I'm really not interested in having you put me down here from
behind your keyboard in ways you'd probably never do to my face. So,
gentlemen, I tnank you (sincerely) for your assistance, as I said it
appears to have fixed the problem (we'll see). Ken, the last word is
yours ... I'm outta this thread.

 

I use penetrating oil all the time to loosen seized fasteners.

This is rather different from pouring it into an engine and adding it to
the fuel, though.

 

This is where we got off the track. Just for the record, you DID ask:

And then when I offered other possible causes, you dismissed them all
out-of-hand.
I may have over-reacted a bit but that kind of exchange is VERY frustrating.

I think it was ME who supplied you with the "Fix".
We should have stopped the discussion there!
Hope it holds up.