Help required - gray smoke and engine rattle

[wernwilk]

Hello all,

new to the forum, I have a family member who is not too mechanically inclined who has a 2003 enfield bullet 500.  (Not a good combination I know).

Anyway, as the 'family wrench' I have been landed with the job of diagnosing and hopefully fixing the problem.

i know there is a lot of knowledge on this site and wanted to know what to look for specifically on this motor.
I was going to do the standard compression test then inspect the rings and valves.

Is there anything else I can do to rule out or indicate the fault here please?

Many thanks.

 

[ace.cafe]

Well, the lack of clues leaves it pretty wide open.

The gray smoke could be as simple as being too rich.
The rattle could be the normal noise from the valve lash, because we have solid lifters which have .012" lash when they are hot. They make noise.

We don't really know for sure if anything is actually wrong with it.

[LarsBloodbeard]

What does the spark plug look like?  Does the smoke go away after a minute?

[PiggyPup]

Well, I can tell you that this is a similar situation to what I had recently, and my new friend Chumma got to the bottom of it quickly and effectively remedied the problem.

My valves were simply too loose, and that was the reason for the excessive rattle, as well as the gray smoke that was the result of unburned fuel from every power stroke.

My Daphne now runs better than ever.

[wernwilk]

Thanks for the tips so far...I have received the bike to look at and once the battery is fully charged I will run the bike and see how it sounds.

Interesting to note that no one thought the worst when I mentioned the rattle and smoke.....good to know.

Out of interest, does anyone have a rough idea of what the compression should be on one of these?

[barenekd]

Out of interest, does anyone have a rough idea of what the compression should be on one of these?

140ish seems pretty common.
Bare

[wernwilk]

thanks all for the great feedback.
I am afraid I have been slacking and have just got the bike fired up...first thing to address is the terrible exhaust blow at the exhaust port....with that quietened down I could listen to the motor, (he forgot to mention that....or that could even be the entire issue)!!

I did notice on exhaust removal that its a simple clamp at the head of the pipe...it does not however seem to attach to the engine head in any way and seems to just butt up against it....is that normal?

Thanks fella's.

[LarsBloodbeard]

I did notice on exhaust removal that its a simple clamp at the head of the pipe...it does not however seem to attach to the engine head in any way and seems to just butt up against it....is that normal?

That is correct.  The exhaust pipe kind of just jams in there.  The clamp is really not that useful, though many people put them on.

[wernwilk]

interesting...well whatever the clamp does I now have to find another one as this one snapped today....whoops!!

Anyone know where I can get one and other Enfield parts?

Thanks.

[Arizoni]

Call Nfieldgear at 1-800-358-0938

They will know what you need and if they have the part they'll get a new part sent to you.

[The Garbone]

If the exhaust is leaking at the joint to the head the money for that clamp would be better spent on a medium pipe expander and rubber mallet to fix the leak.  The clamp is not functional.

[wernwilk]

Okay,

update, performed the compression test, comes in at around 60...not good!!

The plug is oily and coked up...I removed the rocker covers and noticed there is no clearance on the exhaust valve....this would explain the low compression right?
I could not see how to adjust the valve clearance...can anyone shed some light on that for me please.

If I get some clearance in the exhaust valve and the compression is still low....I am going to pull the head and barrel.
Any tips or tricks to this??

Thanks.

[The Garbone]

You have to check the valves using the tappet cover on the right side of the motor and not at the rocker blocks.

Pull the little cover so you can watch the pushrods. Use the kicker to slowly move the motor so the piston is at tdc and you will see that both pushrods will be in their lowest possible state.

Once at tdc and with the pushrods all the way down you set the gap by using the nut adjusters on the bottom of the pushrods.  Set them cold so that they spin freely but have zero up and down motion.

Just for fun here is a picture of my intake pushrod after it jumped off the tappet when I dropped my intake valve seat.  Not fun.

[LarsBloodbeard]

In that case, you might not want to worry about what the plug looks like until you sort out that the pushrod lengths are correct.  And as Garbone pointed out, this is not done at the head.  Adjust the lengths so that you can't move them vertically, but you can rotate them (by hand).  Doing this adjustment requires 3 wrenches.  One to keep the rod from spinning (top nut), one to loosen the stay nut (the small one in the middle), and one to hold/adjust the cup (nut at the bottom).  It may seem like an exercise in futility till you get used to doing it.

[ace.cafe]

Okay, I have to catch up  a little here.

The exhaust leak will need to be fixed. We have methods for this.
And that finned exhaust "clamp" is nothing more than a visual accessory. It never came with the bikes, and it doesn't do anything. Some people like the looks. You can leave it off.

But for now, we need to to do a wet compression test, to see if the low compression reading is from valves or rings. You have a 60psi figure now, which I assume was taken with a few crank-overs with the throttle WIDE OPEN. That is important.

Normal compression on the regular Iron Barrel Bullets is around 110psi.

So, then we read that you have oily plug and stuff, and low compression, so we want to see if it's rings or valves. Take out the spark plug and drop about tablespoon, or two , of engine oil down into the cylinder, thru the spark plug hole. Put the compression gauge back on it, and do another compression check. If the compression comes up around 90-100psi, then you have ring problems. If it only goes up a little bit, then it's probably valve issues. It's going to go up a little bit in any case, because the oil will seal any rings a little better, and make the compression about 5-10psi higher. It's a bigger increase that you're looking for.

So, once you have that info, you can proceed.

Sometimes taking the head off can be difficult, and sometimes taking the barrel off can be difficult. But, other times it's easy. So, just have a go at removing the top end, if for nothing else than a de-coke, and have a look at all that is in there.
If you can't get something off, just ask.

DO NOT hammer or lever on any fins. Ask here for the accepted techniques to get these things off, if you have trouble. The fins will break off very easily, so don't whack on them.