Saturday, April 10, 2010

BRP runs - BUT!!!!!!!

First of all, thanks Kevin for coming round yet again to give me a hand with BRP.

Also, thanks Dale for your help over the phone (MOTL).

Just before Kevin arrived I checked there was fuel in the carb float chambers - three was and it was all clean.

Then I pondered on everything a while followed by fitting the battery and turning the car over. At least this time it backfired through the exhaust which seemed a step forward.

When Kevin arrived we went through all the checks we could think of - at tdc cam alignment marks in line, rotor arm pointing at number 1 etc.

Likely cause number 1

But then there was no spark at the plugs so looking in the dizzy cap we noticed one of the posts had been scored badly by the rotor arm- aha! Faulty replacement rotor arm must be the cause especially when I remembered that the electronic ignition module had been damaged and two wires worn through.

So, replacement old Lucas second hand rotor arm fitted and we gave it a go. No joy although we were now happy about the spark at the plug leads.

Likely cause number 2

Back to fuel - but then spraying Easy Start made no difference and if it had been fuel this would have sorted it, at least for a short time.

Likely cause number 3

Checked the static timing, then found it should be at 14 btdc not 10, adjusted it and still no go.

Likely cause number 4

Now it's time to call a friend - Dale of Moordale Motors. We discussed everything we had done so far and even held the phone over the engine while we tried to start it. Dale immediately said it was a timing problem and that we were well out. He then came up with a really good one - check the points aren't opening after the cam lobe and not before it.

So we did and he was right you know! Further advice over the phone and we moved the dizzy one tooth so we could get it set up right - job done surely. Err - no.

Likely cause number 5

The car sort of now ran on a couple of cylinders and we were scratching our heads. I said to Kevin "what else could make the timing so far out?" He being more mechanically minded than me listened, thought about it and said "let's check the dizzy".

Doing this the rotor arm was now pointing in a different place when at tdc - aha, eureka! Of course, change the plug leads in the dizzy cap to new positions and Bob's your uncle. And you know what, - it worked, BRP fired up!

But what's that horrible loud rattle?

Problem 6

Sorting the rattle out - my theory was I hadn't tightened the timing chain guides up and they were slapping against the chain. Or maybe there was a horrible problem with the jackshaft.

Then again, it could be in the cylinder head so we whipped the rocker cover off.

Aha- one of the cam shaft sprocket bolts had come out (gulp) and the sprocket was very very loose. No wonder there was a horrible rattle. One longer bolt found and fitted as a test and we fire it up again in all confidence that all will be well.

The rattle's still there!

What more can be thrown at us?

Time now to give a little time to pass methinks before returning to this one. The positive thing is that the car now runs, on the negative side there's a horrible loud rattle/knocking and the camshaft sprocket bolt that was in place is now probably in the sump!

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