• Hi Guest!
    You can help ensure that British Car Forum (BCF) continues to provide a great place to engage in the British car hobby! If you find BCF a beneficial community, please consider supporting our efforts with a subscription.
    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

remind me it's fun. good idle. rough when accelerating

Share this page

skystryd

skystryd

Freshman Member
Country flag
Offline
ok...still fun if I could work out what is going on with 'boop'. I did remove (marked) and replaced (tdc) distro. changed plugs/wires/coil. checked plugs for spark..ok. one plug goes where one should go on distro...rest the same. I did put a very light coat of petroleum grease/jelly (vasoline) on distro stem in order to get it to settle in the tube. starts and idles great @ 1K. Attempts to push it beyond idle result in real rough jarring and missing.
coil first? timing 180 out a possibility? recheck plug gaps?
any assistance very much appreciated. Nice weather coming up and I'd hate to miss the chance to get boop out and about.
 
can we have a little more information?

1. what colour are the plugs?

2. which engine?

3. what carb?
 
my apologies...those things are rather important.
1. black 2 and 4 more so
2. 1500
3. Zenith-Stromberg 150-CD4T
 
Thanks! How long have you had the car? Is this a new issue? Is the smog equipment still on it?

Sounds like it is running rich if the plugs are black.

As a first step block off part of the air intake and see if it runs better.

IMHO later Zenith Stromberg carbs are difficult to set up properly. I could never get mine to work right. They seem particularly susceptible to changes in air intake - so if the air filter is different or the smog equipment is removed, it seems to throw it off.

You might want to consider a longer term solution of an SU. The rear HS4 off an MGB has the same bolt mounting pattern and needs about 10 minutes with a file to make fit. I did that and it transformed the car.

In the meantime though - clean the plugs, block off some air and let us know what happened.

cheers!
JP

PS it can be good to put you car info in your signature (where you have your air force info) saves endlessly repeating yourself.
 
A few things on your carb. If a plastic float they can fail and fill with gas and sink flooding carb. And two The diaphragm may have a hole in it making it lean. Question does the choke help?? Next check any vacuum lines to dis. The Distributor has a few moving parts, a vacuum that mover a plate and a set of flyweights plate One will advance spark and the other will retard depending on RPMs and vacuum from motor. The spark plugs will show end results the problem is most likely ahead of plugs. a simple crack in Dis cover seen by a white line in crack can give many problems also.
There is of course one other answer what did you do last. Just saying we make our own problems some times. MF
 
If you're not sure if you're running rich or lean, you can pick up a Gunson Colortune for around $50. It's a see through spark plug that will show different colors base on how lean or how rich the motor is running. Eventually, you start to get a feel for your motor and can tell the mixture based on how the motor is reacting.

I was a clueless novice when I first bought my 1969 Sprite basically on a whim. The Colortune made a great "crutch" for me until I really learned to get a feel for the motor. I might not have my dual HS2s dialed in perfectly, but they're close enough that driving is enjoyable.
 
I'll second the ColorTune recommendation. Have had a pair in the toolbox for decades, used 'em in the shop on customers' cars. Two because a twin-carb setup can be done more quickly. Still had to "juggle" with a 4.2 Jag's three SU setup but those were infrequently seen.

Another of Gunson's "low tech" but really useful tools is an "Eee-Z-Bleed" brake bleeding kit. Makes a one man job of LBC brake system work.
 
Back
Top