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Dampers popping out of the dashpots [w/ pictures]

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Re: Dampers popping out of the dashpots

Check the TIMING................
If the intake valve(s) is still partially open when the plug fires it will back fire out the intake, i.e., timing is too advanced.
Again check the TIMING. It was mentioned earlier but I saw no reply that you have checked it. Again with advanced timing there will be less and less power as the revs go up because the distributor will be adding more advance.
 
Re: Dampers popping out of the dashpots

I've ordered new dampers to stop them from coming out, so thanks for all the advice regarding that.

And I have considered timing, Biff, and I'm a little worried about that. Unfortunately I have the car up at my school now, and don't have all my tools. Is there any way I can check the timing, and, if not, do I have to take the car to someone who has worked on british cars, or will any mechanic be able to fix this?
 
Re: Dampers popping out of the dashpots

You know, there's a piston under that damper...& its not real tight but its not loose either...so for something like a backfire to blow that damper off - you'd definitely know if the timing was off!
 
Re: Dampers popping out of the dashpots

Just checked, DrEntropy, and WD-40 didn't affect the engine when sprayed on the throttle shaft (I could try with some carb cleaner, though), and there isn't much slop in the shaft either.

Hm, I'm not sure I follow, Tony. The damper isn't loose, as you said, but a backfire or just continued pressure seems to force it out--do you mean this could be a timing issue, or if it was a timing issue I'd know it, because it'd be so severe?

If it happens w/ the new dampers I'll pull the choke, and see.
 
Re: Dampers popping out of the dashpots

IMHO, if it were a timing issue, you'd definitely know it!
 
Re: Dampers popping out of the dashpots

Now, I've been known to be wrong from time-to-time though....
 
Re: Dampers popping out of the dashpots

You can set timing with a 12V test light. "Static timing." Engine stopped, IGNITION OFF, rotate the engine by hand to line up the pulley mark and pointer to show 8° BTDC. Remove the distributor cap, clip one lead of the 12V light to the LT lead going to the dizzy from the coil, ground the other lead of the light. Slack off the clamp bolt on the dizzy base, turn the ignition to the "ON" position (DO NOT CRANK), "jiggle" the rotor shaft thru some motion and observe the light. If it blinks off 'n' on it would be VERY close to right... You want the distributor turned to the place where the light JUST comes on, the place where the points ~just~ break, with the shaft/rotor against the "unsprung" stop of the advance plate... Lock it down and reassemble cap. The timing will be nearly perfect this way. It would not surprise me to learn Doug L, or another BCF member has a much more comprehensive tretise on the static timing method.

A couple of quick links:
https://www.mgcarclub.com/CNY/electrical_systems.htm

Good description half-way down this page:
https://www.metrolinamgcarclub.com/tuning101.htm

Good luck!
 
Re: Dampers popping out of the dashpots

DrEntropy, both of those sites were immediately bookmarked--as soon as I finished reading them. I hope I don't need those directions to get the car running well before I get it home (I'd feel much better doing all this in my garage), but your advice and those sites may come in extremely handy.
 
Like everyone says, it is probably just a matter of worn threads on the plastic caps. But if you think that they are okay you might try this. Remove the offending dash pot and turn it upside down over a sheet of 120 grit wet/dry sandpaper on a sheet of glass. Stroke the pot squarely across the paper enough times to produce a very flat and sharp surface to be presented to the plastic cap seat. Wash the chamber thoroughly in hot soapy water and rinse with hot water. Re install it after adding your choice of oils to the piston cylinder up to about 3/8 inches from the top. Use only your fingers to tighten the damper cap. Hope this helps! Jack BTW: If you have those chrome chamber covers trash them before anything else. They don't go down all the way on the bells and will leave only about 2 threads for the damper cap to work with.
 
Oh, what a great idea. thanks
 
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