Esky_gurl Posted December 7, 2009 Share Posted December 7, 2009 My Mk2 Escort Van has decided to have some fueling problems the day after I get its WOF!! It doesnt have the stock engine, follows are some specs: 1600cc engine with ported inlets, 2ltr Cortina Valves, which have been shaved to fit. Hardened double valve springs and hardened valve seats. The carb fitted came with the head - choke butterflies has been removed. Ok so I first noticed there was a problem when I would come to an intersection and idle, When i put my foot down to take off nothing happened, i had to pump acelerator to get any revs. (We have since played with air-fuel and it doesnt do this anymore) Then it started running like it was runing out of gas, kind of spluttering down the road when doing 50kmph. Now it is backfiring through the carby, and running rough as guts when you put your foot down. But it idles fine usually, if idling for to long it will splut itself out and wont start again until its cooled off a bit. We have taken carby apart and it appears to be fine, tho am trying to get a new float as there are a couple hunks taken out of the one in there. I have replaced the condenser, didnt have any effect on the problem. Does anyone know what the problem may be?? Quote Link to comment Share on other sites More sharing options...
Unclejake Posted December 7, 2009 Share Posted December 7, 2009 It could be a torn accelerator pump diaphragm or a massive vacuum leak. Quote Link to comment Share on other sites More sharing options...
m0ss4yy Posted December 8, 2009 Share Posted December 8, 2009 Yeah i'd look for vacuum leak first Quote Link to comment Share on other sites More sharing options...
Hemi Posted December 8, 2009 Share Posted December 8, 2009 double ditto Quote Link to comment Share on other sites More sharing options...
Spencer Posted December 8, 2009 Share Posted December 8, 2009 yup when i had vacuum leaks and a slight blockage in the carby, it had the similar symptoms lean backfires and would only idle on the choke. Spraying around carb/manifold with carb cleaner is a easy way of finding a leak, you will hear it idle up when it sucks some of the cleaner. Other than that give your carb a soak in solvents then a mean blow out when its appart. Quote Link to comment Share on other sites More sharing options...
sheepers Posted December 8, 2009 Share Posted December 8, 2009 id use the search function. and id check the throttle pump. Quote Link to comment Share on other sites More sharing options...
forced Posted December 8, 2009 Share Posted December 8, 2009 If all else fails, give it a compression test and check the tappet clearances. Steve Quote Link to comment Share on other sites More sharing options...
Esky_gurl Posted December 8, 2009 Author Share Posted December 8, 2009 Cheers for all the advice, looks like Im going to have a fun weekend! Quote Link to comment Share on other sites More sharing options...
Esky_gurl Posted December 15, 2009 Author Share Posted December 15, 2009 YAY thanks it was a vacuum leak Still has a few issues but a lot better! I did discover the air-fuel screws are right in, if I screw them out a few turns it backfires etc. Is this a usual thing, it seems a bit strange their right in? Quote Link to comment Share on other sites More sharing options...
m0ss4yy Posted December 15, 2009 Share Posted December 15, 2009 It will tend to backfire if you unscrew them a little, because its leaning out the mixture.. Quite often with twin carbs you can have one fully rich and its still not perfect, and the other can be fine. Doesnt really matter how far the screw goes in or out as long as it runs properly basically Quote Link to comment Share on other sites More sharing options...
Esky_gurl Posted December 16, 2009 Author Share Posted December 16, 2009 Sorry i know Im being a pain! After running so lovely before it is again have issues. The throttle response is shit, especially when idling. If i put my foot down, nothing, I have to pump it to get rev's up. Someone said above it about accelerator pump diaphragm, does this still sound like it could be this? Thanks! Quote Link to comment Share on other sites More sharing options...
Mick Doohan Posted December 19, 2009 Share Posted December 19, 2009 would you like me to have a look at it ? Quote Link to comment Share on other sites More sharing options...
forced Posted December 19, 2009 Share Posted December 19, 2009 It will tend to backfire if you unscrew them a little, because its leaning out the mixture.. Unscrewing it makes it run richer. Where was the air leak? Your initial diagnosis is no doubt wrong. It's not overfuelling, more likely underfuelling. Checking the sparkplugs will tell. Steve Quote Link to comment Share on other sites More sharing options...
Esky_gurl Posted December 20, 2009 Author Share Posted December 20, 2009 Sorry, Im still learning my mechanics so Im usually wrong haha! Vacuum hose which I replaced was the one which went from Carby to Master Brake Cylinder. It seems to be going ok again, bloody temperamental! It misses still - I replaced leads and plugs, now its down to tuning which i have no clue on Quote Link to comment Share on other sites More sharing options...
m0ss4yy Posted December 21, 2009 Share Posted December 21, 2009 If you want your carbs to be tuned as well as possible, then I'd advise that you take it to somebody who knows exactly what they're doing if u dont. Carbs running properly is vital Quote Link to comment Share on other sites More sharing options...
Esky_gurl Posted December 21, 2009 Author Share Posted December 21, 2009 Yea thats the plan, can anyone suggest a good place to take it to in Hamilton? Quote Link to comment Share on other sites More sharing options...
Hemi Posted December 21, 2009 Share Posted December 21, 2009 yea for the time being 2 1/2 turns out is a general measure to stop it being having really bad if i recall ... the backfire through the intake is a too leaner mixture usually as forced pointed out checkt he plugs and it will tell . then again go see a good canary in hamilton and get them to do it ... far faster in the end cheaper and it will save being on the rag when your not Quote Link to comment Share on other sites More sharing options...
Horse25 Posted December 21, 2009 Share Posted December 21, 2009 what is your points gap like? i had simlair problems of back firing through the carb and stalling and running on so i cleaned all the carb etc, turned out i had no points gap. Just an idea Quote Link to comment Share on other sites More sharing options...
m0ss4yy Posted December 21, 2009 Share Posted December 21, 2009 It seems I have a problem now too. twin carbs. front 2 clyls run from 1 of them, back 2 run from the other. The back 2 are constantly getting wet plugs and it just wont start.. tried making it leaner, choking not choking, checked points and gap and everything. for some reason it wont fire!!! If anyone can help me today thatd be good!!! Quote Link to comment Share on other sites More sharing options...
m0ss4yy Posted December 22, 2009 Share Posted December 22, 2009 Woo problem solved Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.