rotordave

iTrader: (1)

Hi,

Yes, another "won't start" thread, but I'm desperate.

My rebuilt stock (1982) 12A went in a few months ago and it ran well for some time. I haven't driven it yet because I needed to fix a few things up, but every couple weekends I would start it and idle for a few minutes.

Then, ever since I replaced the fan clutch, it won't start. Obviously that is unrelated, but I haven't done anything else so it doesn't make sense that this should happen out of the blue.

Here is a video I took of trying to start it (you can see me pushing the throttle via the OMP linkage if you watch in hidef mode):


Here is a summary of the setup:

All new '82 motor except for eccentric shaft

• Totally stock, inc. emissions, rats nest
• All rats nest hoses in fairly good condition
• New spark plugs (since rebuild) BR8EQ14
• New fuel filter
• Timing was fine when we first ran the motor

Things I've checked:

• Spark at all plugs
• Cleaned points in distributor
• swapped distributor and all leads for known working setup
• Condition of spark plugs (wet with fuel)
• Deflooded with fuel pump fuse out before trying to start
• Float levels fine in carb (again all stock)
• Observed fuel going into barrels when pressing throttle

Observations:

• On starting, a lot of fuel (smells like marine fuel) coming out exhaust, even after deflooding
• When this first started happening there was a little bit more oil than you'd expect coming from the first rotor when deflooding, but that has cleared and I haven't seen it since
• The engine did run on one rotor for a little while when we first started it (very first start after rebuild) - tracked this down to a defective yellow solenoid under the air box (this cuts fuel to one rotor on deceleration I believe)
• When it does run (as in video), sounds like it's running on one rotor - this was happening every time I started it before but after a second it would start to run on both rotors)
• Compression "sounds" fine with spark plugs removed, but don't have compression tester with me to check (checked this on very first start and it was good).
• One of the igniters is brand new, replaced before the new motor went in because I never had trailing spark on old motor
• I did once accidentally mix up the front and rear rotors (1, 2) when replacing the spark leads. Tried to start it twice and realized what I had done when it misfired and wouldn't start at all. Surely you can't blow up an engine doing this...

What I haven't checked (at least, what I can think of):

• Fuel pressure (but it seems to be flooding, if anything...)
• Accurately check compression again (why would this go bad on a new engine?)

If anyone has any ideas what else to check that would be great. It doesn't make any sense - there's fuel, spark and compression (although haven't measured this accurately since motor went in). Could any of the emissions components be messing with this? I want to retain the rats nest to keep it stock.

Thanks in advance.

nofrills

double checked distributor timing?

have you got a vacuum gauge, might give you an indication of how well the engine is sealing... im not sure if the engine cranks fast enough off of the starter for this, never actually checked to be honest

my car did this to me once, i cranked it for a LONG time before i walked around the back of it and noticed the antifreeze dripping out of the exhaust.....

rotordave

iTrader: (1)

Thanks for your reply nofrills. No I don't have a vacuum gauge.

I don't have a coolant leak, the vapour from the exhaust is definitely fuel. It was a blown coolant seal that made me rebuild the motor

Is it possible to check timing when running only on the starter?

Was hoping for more insight, maybe everyone is as stumped as I.

andernamen

iTrader: (2)

Well, the engine did start briefly, so you are getting spark, and timing should still be okay. I would look at a major air leak or hose disconnected and/or a fuel issue. Definitely check your fuel pressure and volume. You also may want to consider doing a compression check to ensure something didn't go wrong with the rebuild.

rotordave

iTrader: (1)

Hi. To close this off, I tracked it down to the anti-afterburn valve hose. It was hard and wasn't allowing a vacuum to build, so the valve was stuck down and letting air into the front rotor.

Replaced the hose and now it's fine. But I still have problems with it running too rich and flooding...