Help required - gray smoke and engine rattle

[wernwilk]

great advice guys, thanks.  I will proceed in this order;

1) wet compression test with throttle wide open.
2) valve clearances by method given in text

Then I will post the results/findings and from there probably remove the top end to see for myself what is occuring.

I'll be back with findings.

Thanks.

[wernwilk]

Hi,
an update.  Firstly thanks for all the great advice and help, its much appreciated.
Ok, so I re-did the dry compression test....this time with WOT, it came in at 115psi....I feel an idiot for doing it with the throttle closed to start with!!  Not sure what I was thinking.

So Dry test = 115 psi and the wet test =145 psi

I checked the valve clearances and the push rods spun freely with the piston at tdc without any up and down play.

So, this sounds like a healthy motor right?
Perhaps the problem that was reported to me was in fact the exhaust blowing worse and worse.  When I took a look into the exhaust port I did notice some oil on the exhaust valve stem....would this indicate valve guide oil seal failure....and could perhaps explain the smoke?

Not sure where to go from here until the exhaust is sealed some more and then I can hear what the 'engine noise' was supposed to be?

Any other suggestions while I'm in here.  I am hesitant now to pull the head and barrell as the rings and valves check out on the compression test?

Thanks again. 

[LarsBloodbeard]

Burnt oil being especially prevalent around the valve guide and forming a flowing pattern in the direction of air flow definitely would be a leaky valve guide seal.  See if you can shine a flashlight into the exhaust port and snap a pic for us. 
If that is the case it's not a huge deal.  Grab a new set of guides and toss the head at your favorite machinist.  Should be cheap (maybe $50?) for them to pop out the valves and install new guides and do a valve job.

[Lwt Big Cheese]

Does this bike run?

If so, I'd be tempted to ride it and forget these things until:
a) They get worse
b) You realise that it will never run like a japanese sewing machine.

 

[PiggyPup]

Yes, I would ask this:  Exactly HOW freely do they spin?  If you look at an earlier post of mine, you will see that I had mine adjusted so there was no up and down movement, but they spun VERY freely.  This led to the exact conditions you have mentioned, but when Chumma adjusted mine so that the spin was a bit less, the bike quieted down, stopped spitting gray smoke, and it has more power now than ever.

[ace.cafe]

From that compression test report, it seems to me that you might have a high compression piston in that engine. A normal Bullet will not blow 145 psi on a compression test, wet or not.
I would have a look into that cylinder to see what kind of piston is in there. It could make a big difference.

As for the wet exhaust valve, it might have a leaky stem seal, if it in fact even has any stem seals.

What year is this bike?
What is the history of it?

[wernwilk]

I'll try and answer the questions as they came in;

- yes the bike runs, starts ok and has started to make more engine noise and blow some gray smoke which clears a little as the bike gets warm.

- the bike is a 2003 bullet, 2nd owner who is a novice rider and began his riding career on the Enfield, (brave soul).

- The pushrods spin quite freely to the touch...is this too freely, if there should be more resistance how much?

If I go ahead and tear down the top end, are gaskets etc readily available?  Also, what is the fix for the blowing exhaust mainfold please?

Thanks, you've all been great.

[The Garbone]

Spin sounds good as long as there is no movement. 

I would ride it a bit and check oil usage.  Does not sound like a show stopper,  maybe a little rich.

[wernwilk]

I have attached a photo of the exhaust valve from outside the head...it may not show it too well but there is definately evidence of oil there, however it was more evident before the compression test.

Considering the compression I got (115 dry and 145 wet) I am thinking that I will do the following;

- Adjust the valve clearances a little so that the pushrods do not spin so freely...(at present they spin very easily to touch but no up and down play)
- fix the exhaust manifold blow and listen to the engine easier...any advice on this fella's?
- ride the bike and give it a good test to see if I can hear the noise that my friend is talking about.

I could strip down the head but I am thinking that if the piston and rings are in decent condition, (i.e; the positive compression tests), and the engine is basically sound it should be safe to ride.

Again, all and any help most appreciated guys.

[ace.cafe]

The exhaust port looks fairly normal.

There are 3 basic ways to fix the exhaust leak.
#1) Get a muffler expanding cone and use it to expand the header pipe to be a better fit in your head.
#2) Use some thin sheet metal(like a beer can) and cut a piece to wrap around your header, where it goes into the head. This fills the gap.
#3) Use some glop like silicone sealer to fill the gaps. Then let it sit for 24 hours to cure, before using the bike. This will need to be re-done periodically.

Yes, gaskets are readily available if you want to tear down. It would be nice to know what piston you have in there.
Your compression test showing 115 psi dry, and 145 psi wet, could indicate a high compression piston with bad rings.

[Lwt Big Cheese]

I believe you should be able to turn the pushrods with your fingers as apposed to spin freely.

Small point I know - and I may be wrong 

Also, I believe these bikes have the ability to perform well with huge amounts of abuse. You may be striving for perfection when you just need OK.   

That's why I suggest riding her a bit. If she performs OK then don't worry. If things are bad she'll tell you.

[LarsBloodbeard]

Yeah, that looks like a leaky valve guide to me.  That would probably be the source of your smoke.  Overall the port looks good though.  It's not a huge deal, but I would fix it.

To answer your question about availability: parts are quite easy to come by.

[Arizoni]

I would ride it as it is providing it doesn't lay down a cloud of smoke for more than 1/2 mile after starting it.

With the smoke (apparently) coming from the exhaust valve guide there is little chance of fouling anything except the grill on the car that's following too close.

If the smoke cloud is still there after riding a mile or more, the oil wiper ring would be suspect.

For now though, just ride it and enjoy.

[wernwilk]

again great advice guys.
I will be riding the bike to check on smoke amount and also oil usage.
Then depending on what is found I may strip the top end as required.
i will post results and findings as I get them.
Thanks for hanging in there with me fella's.

[wernwilk]

Just an update - So I used a pipe expander to get a great fit at the manifold and cut down the excess noise.  I started the bike and it most certainly has a death rattle coming from the cylinder...a harsh sound that is for sure not the norm.

I will be tearing down the top end and seeing whats wrong.

Also, once i had turned the bike off, the starter was still engaged....not good.  Not sure if it was engaged the whole time but either way not gonna help it.  Ha anyone had this sort of starter issue/short before?

Thanks all.