More than a year ago, I bought off ebay a replacement engine for my '89 Hurricane. I haven't had the time to work on it since then, but yesterday I started working on it again.

About the new motor: it had only one pulse generator, so I concluded it's a '90. On the front it had the emission control air suction valve. From what I've read, I believe it to be a California engine.

About the bike: old engine had no emission control, spark unit (CDI) has 6+4 wires, two pulse generators and sprocket with 9 teeth

Current state: installed the pulse generators and the pulse sprocket from my engine on the new engine, removed the emission control from the new engine (sealed the hole near carb #4 with a screw, the holes near the exhaust are opened - will seal those too)

So back to the problem in hand.
Yesterday I spent the entire day trying to start the engine.
- I used a recently charged car battery for the job
- cleaned the carbs
- used new gas (gravitational feed, my bike had no fuel pump since I bought it, also removed the fuel filter since it was clogged)
- the spark plugs all have spark (but I find it to be a bit weak)
- engine cranks but will not start

Considering it's a California engine, is there anything else I should do ?
Could the fact that I haven't sealed yet the holes from the emission control have anything to do with the engine failing to start ?
Regarding the valve timing or anything else ?

Please help !

 

Are you sure youre getting fuel through the carbs? With gravity feed it will take a long time for the bowls to fill up. Try pouring a bit of gas down each carb opening. and by bit I mean A LITTLE AMOUNT. If you are getting spark, then its a fuel issue. Also, are you sure you have the plug wires in the correct cylinder?

 

Yes, the wires are paired correctly, 1 with 4 and 2 with 3.
I was thinking of using a syringe to pour gas in the carbs, like you said.
Also, it crossed my mind to try using starting fluid as a last resort if gas alone doesn't work.
Will try again when I get home from work.

Later edit:
I got home, used a syringe and poured gas in each carb.
After that, I took out the spark plugs, they were fuel fouled. I dried them, and repeated the process after testing the spark.
I also used a starting fluid spray.
After multiple attempts, all I got were some flames out the exhaust and some backfires through the carbs.

What else could I try ?

 

Check your ignition system first as per the troubleshooting portion of the Haynes Manual.


If youre getting backfires through the carbs and youre positive you have the plug wires on correctly, it appears that the timing is off. Has this engine been rebuilt? This is a bit of work, but theres 2 ways you can check this. You can either remove your carbs, OR Remove the valve cover. (I would go the valve cover route because if the timing is in fact off you will have to remove it anyways)

Once you can see the valves, remove the access plug in the clutch cover on the right side of the engine so you can get access to the engine crank shaft bolt. With a ratchet and socket on the bolt, rotate it clockwise until you see the timing mark on the crankshaft and it lines up with the timing mark on the inside of the inspection hole. This should be at TDC on the compression stroke.

While watching your intake valve on cyl 4, rotate the engine 360 degrees (one full rotation) and when you complete the rotation, your Intake valve should have just closed. If it hasnt, your timing is off and you need to move the cam shafts.

 

I don't know if the engine has been rebuilt. I bought it from ebay, it was shipped to me from Germany (I'm in Romania) and I was told it was in top condition. I also got a compression chart with it but I can't manage to find that one. If it's necessary I'll have the compression rechecked.

I did the testing using Chapter 5 in the Haynes Manual. Here are the specifications I found in the manual, and the readings I got.

Pulser coil resistance 460-580ohms
White/yellow - yellow 515ohms
White/blue - blue 535ohms

Ignition HT coils primary 2.5-3.1ohms
Coil #1 3.4ohms
Coil #2 3.4ohms

Ignition HT coils secondary with lead and cap 21-25kohms
Coil #1 23.9kohms
Coil #2 27.2kohms (I found one of the leads to be damaged, I switched it with a good one and the reading was 24.5kohms)

Ignition HT coils secondary without lead and cap 11-15kohms
Coil #1 14kohms
Coil #2 14kohms

I also removed the valve cover and I aligned the timing marks in the inspection hole. I didn't quite get that last part about watching the valve, better said, I didn't know how to watch it. Could you maybe explain a bit ? The valve cover is still removed, so I'll be able to try again.

I checked the marks on the cam sprockets.
The mark on the exhaust camshaft sprocket is aligned with the head surface.
The one on the inlet cam sprocket seems to be a just a little lower than the head surface. I'll check again to make sure I perfectly aligned everything and it's not just an impression.
The camshaft lobes near cyl #4 side are both facing outside.

Here are some pics I made, sorry for the poor quality, I took them last night with a low quality camera.

What conclusions should I draw, is it possible that the problem originates in the small differences on the electrical part ?

 

I'm not trying to call you an idiot, but are you 100% sure you have the plug wires going to the correct cylinders? It's very easy to switch them around (believe me, I've done it) Backfiring though the carbs is a telltale sign.

I don't think the small difference in ohms would cause a no start situation. The numbers given in the manual could be different than yours simply because of air temp, temperature of components, or maybe your meter is just a little off. As long as you can see a nice blue/white spark and the gaps are set correctly there shouldn't be a problem.

My guess is either a timing issue or a compression issue. Your inlet sprocket does seem to quite a ways off though, I'd check into that first.

 

First thing I did today was to recheck the inlet sprocket. Turns out I looked at it and took the picture from an angle that made it seem to be off. Looking at it perpendicularly, the sign is aligned with the head surface.

The spark wires from coil with yellow/blue and black/white go to cylinders 1 and 4, and the wires from the coil with blue/yellow and black/white go to cylinders 2 and 3. I count cylinders 1-2-3-4 from left to right, from sitting on the bike position.
I believe this is correct.
However, I did switch them just for the sake of testing, and while in the right position I got some flames and booms and bangs, with the spark wires switched, there was a explosion-like sound, but no flames, no smell, nothing.

I would have been glad to be an idiot and to have my engine running right now. I guess the next thing to do is a compression test.

 

Yea you nailed it, the left side coil runs 1 and 4 and the right side coil runs 2 and 3. And your cam timing looks fine. Just throwing this out there, but are you using new spark plugs? Also, are you using the original CDI (6+4 wires)? If so, did you swap back to the original dual pulser coils?

 

Yes, I'm using new NGK DPR8EA-9 spark plugs. Yes, I'm using the 6+4 wires CDI. Thanks for bringing up the dual pulser coils !

From my last post, I bought a compression measurement tool and measured the compression on the engine.
With the engine cold, cranked until the needle stopped raising (highest read), my readings were 152PSI - 148PSI - 160PSI - 160PSI. I also poured some oil in cylinder #2 and got 183PSI, so I'm guessing the rings are a little worn out.
Anyway, the readings indicate my compression is near the 157PSI limit the manual specifies (185 - 28). It's a little worn, but I thought it should start.

So, I had spark, I had fuel (fuel fouled sparks) and I had compression.
The only thing that came in mind was a lack of syncronization between the compression and the spark.

I remembered that when I installed the new engine and checked the wiring, I switched two wires in the red connector from the pulser coils that weren't in the right position. So I took off the left crankshaft cover, found a picture of the coils on an ebay auction, compared the wire colors in mine and in the picture, and there it was !

My pulser coils were reversed inside the crankshaft cover !!!
I switched them to the right position, and the engine fired.
So, before anything else, I want to thank you guys for your advices !!!

However, although the engine starts, it stalls immediately after. And it does not start again only after numerous attempts. Also, the plugs are fuel fouled.

My guess is the carbs.
Before taking them off, I noticed carburetor #3 did not leak any fuel when I loosened the drain screw.
I took them off, took them apart (throttle stop screw, vaccum chambers and float chambers, last time I only cleaned the jets). I did not separate the carbs. Should I separate the carbs ? What should I look into when reinstalling the carbs, what adjustments should I make ? Am I right thinking that the problem is carb related ?

 

Yup I would say your carbs are in desperate need of a good cleaning. I had the problem of number 3 cylinder getting fuel fouled. I ended up getting a new rack of carbs. First things first, clean your carbs really well removing the needle seat and ensuring the filters are clean, remove the choke slides and ensure they are nice and clean, remove the jets and make sure they are clean. Ensure that when you put them back together that your throttle plates are all adjusted to roughly the same, and that your fuel mixture screws are 2 1/4 turns out.