A Canadian lost overseas

Recreateme said:
... Even so, if there isn't compression, I would think you're plugs should still be wet with fuel if you are getting fuel in the cylinders right?
Click to expand...
I was thinking the same thing and then it occurred to me that it is the vacuum created by the piston going down (with the intake valve open) which ultimately sucks the fuel in.

There could be a total blockage in the fuel line (maybe a bee's nest?).

But, if not, and if the plugs are dry, then it must be because there is no sucking (zero compression) or the intake valves don't open, or they open at the wrong time in the pistons' cycles. Non?
 
To sum up at this stage:

dry plugs AND not firing when spraying brake cleaner into the intake can mean:

1. no compression at all - this would explain both but would mean you are in for a fair amount of work. Could be that your valves are out of spec, shot or bent, could be that your piston rings are not sealing at all.

2. The brake cleaner test failed for some reason AND you're not getting any fuel into your carbs. Check the float bowls, they should be full of fuel. If not, your inline fuel filter (if you have one, you should install one if you don't) or your petcock is clogged, or your float needles or floats are stuck.

3. The brake cleaner test failed AND your carbs are still not clean - there could still be a clogged jet which you missed which is causing all this, although I would expect after a rebuild to at least get it firing once or twice

4. Your plugs appeared dry but were actually moist from the brake cleaner AND you're not getting spark under compression. There's no real way to test this other than swapping out the electrical components related to the spark (plugs, caps, wires, coils, etc) with new ones, one by one.

5. Your plugs appeared dry but were actually moist from the brake cleaner AND your timing is way off. Unlikely scenario since one or two fires would have been expected still.

6. You have a major air leak somewhere between your carbs and your cylinders which causes your bike to only suck air. Check by spraying brake fluid around your carb boots when trying to start

so you see, either you screwed up somewhere - or you're screwed... :shrug:

good luck!
 
willem said:
To sum up at this stage:

dry plugs AND not firing when spraying brake cleaner into the intake can mean:

1. no compression at all - this would explain both but would mean you are in for a fair amount of work. Could be that your valves are out of spec, shot or bent, could be that your piston rings are not sealing at all.

2. The brake cleaner test failed for some reason AND you're not getting any fuel into your carbs. Check the float bowls, they should be full of fuel. If not, your inline fuel filter (if you have one, you should install one if you don't) or your petcock is clogged, or your float needles or floats are stuck.

3. The brake cleaner test failed AND your carbs are still not clean - there could still be a clogged jet which you missed which is causing all this, although I would expect after a rebuild to at least get it firing once or twice

4. Your plugs appeared dry but were actually moist from the brake cleaner AND you're not getting spark under compression. There's no real way to test this other than swapping out the electrical components related to the spark (plugs, caps, wires, coils, etc) with new ones, one by one.

5. Your plugs appeared dry but were actually moist from the brake cleaner AND your timing is way off. Unlikely scenario since one or two fires would have been expected still.

6. You have a major air leak somewhere between your carbs and your cylinders which causes your bike to only suck air. Check by spraying brake fluid around your carb boots when trying to start

so you see, either you screwed up somewhere - or you're screwed... :shrug:

good luck!
Click to expand...

Haha after reading that, I feel more along the lines of being screwed. :thumbsup:

All good though, because this stuff can always be fixed one way or another. It might take a little longer than I expected and I might have to buy a lot more parts than expected, but I'm sure this one can be revived.
 
ryMY said:
... I feel more along the lines of being screwed. :thumbsup: ... I might have to buy a lot more parts than expected, but I'm sure this one can be revived.
Click to expand...
Could be, but don't buy anything until you confirm that the existing is broken (unless you are in the 1% and can afford to indulge). While it is unlikely that your valve timing is off by 180° it costs nothing to check and adjust so it makes sense to eliminate all the the possibilities one-by-one in reverse order of cost.

Willem raises an interesting possibility - that you have a large enough air leak to allow the bike to suck just air. I don't know how to test that - normally the leak test is done on a running bike and when the brake cleaner is sucked into the leak, the engine idle changes. With a bike that isn't running, just turning over, you might get it to sputter on cleaner sucked in through leaks. But if you have large leaks but not enough cleaner gets in to cause a sputter, you will incorrectly conclude you have no leaks.

You could buy a tube of seasonal draft seal (for old leaky Cdn. windows) and use it to temporarily seal ALL the joins in the air plenums. If it runs when sealed this way, you will know where you need to repair. Afterwards, the stuff can simply be pulled off. .
smiley_emoticons_my2cents.gif
 
im in agreement with the compression issue for whatever reason you have little to none.This could require a top engine tear down to fix the problem
 
When trying to kick start the bike, can you feel resistance? If you try kicking it over with the spark plugs out and the ignition off, the engine should just whirl over with virtually no resistance. With the spark plugs (new ones, right?) installed, there should be noticeable resistance.

An engine only requires 4 things to run - Compression, fuel, air, and ignition.
 
Still true with a Diesel! The ignition is provided by the heat of compression which causes the fuel to combust when injected. And many Diesel engines have glowplugs, which provide a red hot surface that the fuel is injected onto for when the engine is cold. This also counts as an ignition system.

Now, if you'd said "unless it's a Turbine", you would have been close to correct as they are a continuous combustion cycle. And even they have ignition systems for starting, so...

p.s. I used to be an aircraft tech. ;)
 
in winter time without a garage there's little fun in bike building, so we turn to the forum to release our bike related thoughts here :)
 
Thats a good point Leo, if its missing a piston ring or something you wouldn't have compression or vacuum and it wouldn't pull in fuel at all.

I think the first thing to be done here would be remove the plug put your thumb over the hole and give it a kick, or fire the starter to see if you feel anything. If you don't then found your answer, no compression and you need a tear down. If you get something then you need a gauge to determine if its okay or too low.

The other things to look for would be air leaks, in the lines, and carb boots, followed by valve checks to make sure they work and open at the right time.
 
Hahaha man you guys are really wanting to get this bike running! I have been totally busy with reports for school the past days and I couldn't get any spare time to go over there and work on the bike.

I will do this tomorrow and come back with some news for everyone.
 
willem said:
in winter time without a garage there's little fun in bike building, so we turn to the forum to release our bike related thoughts here :)
Click to expand...
According to the news, you are enjoying warm breezes off the North Sea gulf stream in the winter time. :wink2:
Are you putting another stereotype to rest? :laugh:
 

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