Roo
Part of things
'Nina' the German Cortina
Posts: 130
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Basically boys and girls, my Taunus is still sporting her original 2.3 Cologne v6. The block itself has always felt really healthy (this has recently been confirmed)but the original solex carb was shot so a brand new Weber 38 dgas was fitted. At this point it was also found that I'd had an meltdown in the loom @ some point so this was also sorted with a fair amount of new rewiring. Literally on the way home from having these things done she start developing hesitation, noticeable mostly when giving around half throttle, very gentle throttle was ok but cruising at 65-70 you could feel the stutter constantly but less pronounced. This got so bad she would hardly pull at all. Basically we found that the dizzy bearings had quickly deteriorated since last checked and now had considerable play. So that has been changed this wk and while we were at it everything else was replaced from coil through to plugs. In the meantime a red top facet fuel pump and Filter King was added to eliminate pressure being a factor. Weber was also treated to a less restrictive air box. On restart the engine sounded the best I've heard it once timing was set and slightly advanced. Took her down the road, windey lanes so lots of braking and accelerating and she was pulling well but still hiccuping a tad on initial throttle! We removed the vacuum advance and this seemed to reduce this.....but it was still there! But I was thinking I could overlook it as it was minor and....added to her character?!  Waved goodbye to my friend (who restores classics to a high standard) and set off on 15m drive home....... A mile later, and my happiness was dashed, the further I went the more the hesitation crept back in, even causing the odd 'bang' up through the carb. When I hit the open road and settled at higher speed that damn jolting feeling was there again......constantly!  Giving her the beans causes the initial stumbling but then pics up ok although still feels strangled, also the carb is singing sweetly anymore as it once did. Part throttle though shows hesitation, almost missing, all the way through the rev range. Sorry for the essay, but I'm not a mechanic so I wanted to list whatever I can think of to save any extra questions...... The work has been done by respected mechanic though, and even he is loosing patience now! I've read similar issues with use of 38 dgas on various forums but never quite the same. Anyone's help or experience would be very much appreciated. We're having another session wit her nxt wk and I'd like a list of theories to take with me if poss. Thank's in advance. Roo |
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Last Edit: Oct 5, 2012 14:40:28 GMT by Roo
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Don't know if this will help...
I had an issue a few years back with a V8 Rangie... it had been standing for a while, so new plugs, rotor arm, plug leads, dizzy cap etc. She ran beautifully - for about 3 miles, then got rougher and rougher. When I finally limped home it then refused to start. Next day it was running again - for a while.
After much head scratching, a few choice words and a bit of trail and error, it turned out to be a faulty (brand new) rotor arm. Worked perfectly when cold, but as soon at the engine warmed up it would break down so the spark got weaker and weaker until it started misfiring and then flooded.
If you've still got the old stuff you took off it might be worth swapping those bits back on one-by-one and doing a test run to see if it makes any differenct.
Good luck!
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Sounds mixture-realated - I'd say that it's certainly lean on cruise (hesitation). Did you buy a specific carb kit for that engine? If not then it needs re-jetting.
Have you looked at the plugs? They'll tell you a lot about what's going on.
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bortaf
Posted a lot
Posts: 4,549
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check the coil voltage? if the resister wire is breaking down it will get worse the hotter it gets.
is the rotor arm the rev limiter type ? had problems with these before allways changed back to the non RL type.
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R.I.P photobucket
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Roo
Part of things
'Nina' the German Cortina
Posts: 130
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Don't know if this will help... I had an issue a few years back with a V8 Rangie... it had been standing for a while, so new plugs, rotor arm, plug leads, dizzy cap etc. She ran beautifully - for about 3 miles, then got rougher and rougher. When I finally limped home it then refused to start. Next day it was running again - for a while. After much head scratching, a few choice words and a bit of trail and error, it turned out to be a faulty (brand new) rotor arm. Worked perfectly when cold, but as soon at the engine warmed up it would break down so the spark got weaker and weaker until it started misfiring and then flooded. If you've still got the old stuff you took off it might be worth swapping those bits back on one-by-one and doing a test run to see if it makes any differenct. Good luck! Cheers for the reply Davemnw, I do still have all the old parts ale ordered some multiples of new cap, arm etc etc so I'll check the lot again. It's any ideas that get us thinking in other directions that I'm sure will help sort it in the end!  Cheers |
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Roo
Part of things
'Nina' the German Cortina
Posts: 130
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Sounds mixture-realated - I'd say that it's certainly lean on cruise (hesitation). Did you buy a specific carb kit for that engine? If not then it needs re-jetting. Have you looked at the plugs? They'll tell you a lot about what's going on. The carb came straight from Webcon and was the only one they specifying for the 2.3 cologne. I spoke to a chap there just to double check it was correct when we started having issues and he explained it's more often a replacement for the larger cologne's and the 3.0 Essex but it's been jetted down specifically for the smaller lump. I've read conflicting opinions on this carb mated to my engine, but it was more about it over fuelling on a stock lump, which mine is (standard cam etc) In my uneducated opinion, I too would say it feels lean under load and at cruising speed. Ticks over and revs up fine with no hesitation in the work shop! Last time we checked, plugs showed no issues. Think it's time to go back around again though and recheck everything!  Cheers for your thoughts! |
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Roo
Part of things
'Nina' the German Cortina
Posts: 130
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check the coil voltage? if the resister wire is breaking down it will get worse the hotter it gets. is the rotor arm the rev limiter type ? had problems with these before allways changed back to the non RL type. Thanks for the reply.... The coil voltage is defo an area to investigate next. Stationary it is reading fine and my spark is very healthy. But we're going to rig a gauge and run it into the car so he can monitor it while the hesitation is happening out on the road. After this and rechecking all the basics, the carb will be put under closer scrutiny and the fuel tank, just in case it's debris getting kicked up with the car's movement and it's obstructing flow.......?! Cheers for your thoughts guys, everyone's ideas are helping to get us thinking and re thinking! |
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ChasR
RR Helper
motivation
Posts: 10,194
Club RR Member Number: 170
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The Weber 38 DGAS IIRC was fitted to the 3.0 Capris. Generally speaking it seems to be a reliable carb (or at least in the Triumph Stag circles where it replaces Strombergs).
Whilst I was thinking this could be an accelerator pump issue I would check your coil and coil voltage. What resistance does your coil come up with on the primary and secondary windings? Rotor arm is something else I would suspect, especially if it is a pattern item.
Final thing is that you say the the hesitation occurs at part throttle, what if you snap the throttle wide open?
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Last Edit: Oct 6, 2012 8:53:35 GMT by ChasR
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Roo
Part of things
'Nina' the German Cortina
Posts: 130
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The Weber 38 DGAS IIRC was fitted to the 3.0 Capris. Generally speaking it seems to be a reliable carb (or at least in the Triumph Stag circles where it replaces Strombergs). Whilst I was thinking this could be an accelerator pump issue I would check your coil and coil voltage. What resistance does your coil come up with on the primary and secondary windings? Rotor arm is something else I would suspect, especially if it is a pattern item. Final thing is that you say the the hesitation occurs at part throttle, what if you snap the throttle wide open? I will check the resistance on the coil when I pull her out on wed. I couldn't tell u what the reading was last time we checked as I was in the car and my friend Dom was testing this and that in the engine bay. Accelerator pump is something I've heard mentioned on other forums I've read. Also minute particles of dirt and dust getting in here and there. When we were setting her up, there was occasions where the filter top was off for a period and some body filler sanding was being done in same area. I'm thinking blowing everything through and some carb cleaner may be a good idea?! In answer to your question, when the throttle is buried stationary she reacts cleanly with no hesitation, or at least she did before I set off home. But under load she will hesitate initially, then bog down, followed by a slightly hesitant increase in revs and then it seems to improve but she still feels strangled right through the range? |
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Have you checked for air leaks around the manifold and carb?
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Roo
Part of things
'Nina' the German Cortina
Posts: 130
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Have you checked for air leaks around the manifold and carb? Yes daddy (Lol) Sprayed some carb cleaner around both last wk, there was no bubbling or rev increase. But it's going on the list of things to check again! Cheers |
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I had a 2.8 capri, exactly the same problem.....turned out to be thermostat not opening at all, would run fine for couple miles, get slower, lumpier, and then just stop, wait 10 mins, would be fine again........something to do with the auto choke, took the stat out and it was fine, replaced the stat, died again, put in new stat, sorted.
doubtfull its the same thing, but easy to check
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"No............I think I'll stick with the Maxi"
Arther Daley
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Kieran
Posted a lot
Posts: 1,092
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Dirt in the carb (idle jets)?
Coil breaking down?
Ballast resistor / eureka wire breaking down
Valve clearances tight?
Inlet leak?
That's where I'd be looking
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The Ashby Jackson fleet:-
1979 Mini Clubman 1.8 K series
1978 Skoda 110r Project 130RS K-oupe
1978 Austin Allegro 1500 SDL Estate
1984 BMW K100 Sidecar outfit
1999 Yamaha FZS 1000 Fazer
1991 Kawasaki ZXR400 race bike
2002 Kawasaki ZX9r race bike
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djefk
Part of things
Posts: 844
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My advise: Take it to a rolling road so they can see what it's doing under load, cure the issue then set everything up to its absolute optimum for you.
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Roo
Part of things
'Nina' the German Cortina
Posts: 130
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I had a 2.8 capri, exactly the same problem.....turned out to be thermostat not opening at all, would run fine for couple miles, get slower, lumpier, and then just stop, wait 10 mins, would be fine again........something to do with the auto choke, took the stat out and it was fine, replaced the stat, died again, put in new stat, sorted. doubtfull its the same thing, but easy to check I've heard similar stories to yours before and a lot talk about similar probs to mine but not exactly....going to need to check all these things though anyway the way it's going! Thank's for your input mate |
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Roo
Part of things
'Nina' the German Cortina
Posts: 130
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Dirt in the carb (idle jets)? Coil breaking down? Ballast resistor / eureka wire breaking down Valve clearances tight? Inlet leak? That's where I'd be looking Thank's for the reply Kieran. -Dirt in the jets is defo something I want to check, as, as I mentioned previously, there was some airborn dust about when we were fiddling with here, sometimes without air filter top on..... -The coil is brand new and stationary, the strength of spark is very healthy, we will check this while on the move on wed though hopefully. -I checked valve clearances when I first got her and again last wk and they were still spot on both times. -Inlet leak is something we thought we'd ruled out but it does display the signs of being a bit leaky somewhere.....we'll check again. Thank you for your ideas! |
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Roo
Part of things
'Nina' the German Cortina
Posts: 130
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My advise: Take it to a rolling road so they can see what it's doing under load, cure the issue then set everything up to its absolute optimum for you. Djefk, we are moving that way now. My mate who knows engines is pee'd off as I think he's feeling beaten now, he's spent countless hrs checking, re checking and replacing parts to try and cure this.....it's got personal now! Basically we'll just go over it with a fine tooth comb this wk to make doubly sure it's not just a simple over sight somewhere. But after that the next stop will be the rollers. There is a guy we know who's moved his set up onto same sight as a locally renowned old skool race engine builders. Think we can guarantee they'll get to bottom of it!  Cheers |
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ChasR
RR Helper
motivation
Posts: 10,194
Club RR Member Number: 170
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What brand of coil do you have?
On the Stag it started to spit out of the exhaust when it was warm at 3kRPM, sometimes at 2.5kRPM. If you were gentle with the accelerator it was fine. It turned out to be the new coil I have fitted (a County branded item, although I hear Intermotor are not that much better). I guess there is a reason why Bosch coils are pricey (what mine is running now).
However, it seems strange that all of these issues started after fitting the carb. Is it jetted correctly? This is something a rolling road could sort out for you. Unlikely, but what state is the distributor in?
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Kieran
Posted a lot
Posts: 1,092
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Spitting back through the carb and hesitation is normally leaness.
Fuel pump ok?
Fuel filter clear?
Carb filter (under the brass nut near the inlet hosetail) clear?
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The Ashby Jackson fleet:-
1979 Mini Clubman 1.8 K series
1978 Skoda 110r Project 130RS K-oupe
1978 Austin Allegro 1500 SDL Estate
1984 BMW K100 Sidecar outfit
1999 Yamaha FZS 1000 Fazer
1991 Kawasaki ZXR400 race bike
2002 Kawasaki ZX9r race bike
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what were the symptoms that made you change the solex to the weber?
i don't know about these engines, does the weber use the same manifold? are the gaskets compatible, are any /all holes needed in the gasket present? sometimes the carbs breathe internally through holes in the manifold gasket.
are any vacuum or breather hoses blanked off with bolts or in the wrong place?
is the fuel pump ok for this type of carb?
is the coil the right type, if you've fitted a ballast type 9v coil it could be breaking down under the 12v load. or vice versa.
is the choke operating correctly?
lots of questions sorry
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