BVH carburettor base warped
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    Fellow Frogger! CorneSoutAfrica's Avatar
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    Default BVH carburettor base warped

    Hello Everyone!

    I am having some issues with my BVH's carburettor. When I apply my foot on the brake pedal the idling drops as expected, but after a short while it picks up again, just enough to cause the car to creep in gear apart from that the car slowly started to run worse and worse aspecially at idle.

    I also recently bled the centrifugal regulator and brakes and screwed in the big brass screw at the base of the carburettor to decrease idling speed, I felt the screw seated but my idling did not drop much, now that can't be right? If you close the big brass screw your car should be on slow idling, right? With this setting I apply my foot on the brake and only then do the idling drop to the slow idle, I suspect the brass screw is not seating properly....

    I thought that I should maby take off the carby and check the base for straightness with a straightedge... Boy did I get the surprise of my life The base is so warped that I can't believe this car has been running let alone idle!!

    I am not sure what to do now, I could resurface the carby base but what about the brass screw not seating? I guess the warped base also slightly warped the seat of the brass screw. What do you guys suggest? Look for another carburettor all together or try and fix what I have?

    Sorry I have been so quiet, but work comes first and unfortunately cars second. I have been very busy with my Safari but that will be a new thread, very soon!!

    Thanks for your help
    Corne

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    VIP Sponsor richo's Avatar
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    Mill the base flat and try it. That's your first step, then let us know the result.

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    Fellow Frogger! CorneSoutAfrica's Avatar
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    Thank you Richo.

    I do not think the base was ever resurfaced or milled, the reason why I never suspected the carby was because it ran perfect on the safari this system came from. I just bolted the carby with manifold onto my car's engine, because I was afraid of something like this.

    I will report as soon as the caburettor is back on the car!

    Corne
    1968 ID21 break
    1971 DS21 IE BVH Rouge de grenade (Madamoiselle Rouge)
    1974 DS Pallas Sable metalisse My first restoration (Edith) Now BVH
    1973 DS pallas Metallic red. "Rusty"

    1947 Traction Avant

    Modern

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    BVH Roger Wilkinson's Avatar
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    Before you permanently change the base, you could try a "silincon sandwich" carby gasket, the Buttercup Bob cure for that problem. A couple of sheets of gasket paper, some silicon gasket goo in between, then tighten the base so it moulds to the faces. I have not done this, but it sounds as though it is worth a try.

    Roger

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    VIP Sponsor richo's Avatar
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    Roger, the unit was produced with a flat base. It needs to be milled, it is useless otherwise.

    Do not use silicone anywhere in or near an engine where it can be ingested or otherwise be caught in the engine. Bad Roger

    It's like the old saying, if it's got t*ts or wheels it will cost money. Well, silicone ingested by either has proven over time to be a disaster!
    Last edited by richo; 10th May 2013 at 11:39 AM.

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    Hi. I have had problems with my BVH carby tuning ever since I purchased the car. I kept using the procedure for adjustment as per the manual. I was surprised at how screwing in/out the 3 adjusting screws had very little effect. I could not get the normal idling speed down to the rpm advised. I found that the carby base was somewhat warped and so sanded it flat. This had little effect but I did notice that the throttle spindles had some slack in the housing, so assumed that air leakage here was the reason.
    I still had a problem with the engine stalling under braking, when the idling was being reduced too low. Finally I threw away the manual and increased the normal idling speed. This is now around 1200rpm by the dash tacho and speed under braking is around 600rpm. At least it now rarely stalls under brakes and is driveable.
    Logically(?) my next step should be to get the throttle spindle pivot points in the housing bushed. Is this feasible?
    PS - I still find that the accelerated idling screw adjusting has little or no effect.

    cheers, Don
    Citroen DS21 Pallas 1970 Renault 16TS 1976 Renault 5TS 1981

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    VIP Sponsor richo's Avatar
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    Don,
    At the risk of hijacking Corne's thread, yes, it is possible to bush the throttle spindle pivot point.

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    The base of my renault 4cv used to warp ,i found by machining it flat i reduced the thickness ,makeing it more prone to warping ,can a heat proof spacer be fitted under the carb to reduce transfer of heat . Pugs

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    VIP Sponsor richo's Avatar
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    They have a thick gasket.
    To have them warp once in 40 years isn't too bad, they don't generally cause a problem after that.
    On a BVH you also have a CRC attached to the throttle spindle via a flector, a spacer would not necessarily be a good idea.
    You would need to own and understand a BVH to appreciate this factor, err, flector.

    You could of course make a spacer for the CRC too, then stretch the hydraulic lines...
    Last edited by richo; 10th May 2013 at 08:40 PM.

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    Fellow Frogger! denxm's Avatar
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    Quote Originally Posted by richo View Post
    They have a thick gasket.
    To have them warp once in 40 years isn't too bad, they don't generally cause a problem after that.
    On a BVH you also have a CRC attached to the spindle via a flector, a spacer would not necessarily be a good idea.
    You would need to own and understand a BVH to appreciate this factor, err, flector.

    You could of course make a spacer for the CRC too, then stretch the hydraulic lines...
    as michael caine would say, not many know that, .. never heard of a flector..

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    Fellow Frogger! CorneSoutAfrica's Avatar
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    Richo our cars are just that extra bit more special.. and different specially our lovely BVH DS

    I have a bit of a problem. There are no places close by who can mill the base of the carby, i have to go to the big cities to have it done properly.

    I recently aquired a 1970 DS 21 bvh safari. So as soon as I get the car here I will temporarily use that carby while this one is in for milling.

    I want to mill this specific carby because the previous owner had the carby rebushed cleaned etc, guess the base wasn't as bad then as it is now.

    In the meantime I got some flexoid gasket paper, a bit thicker one and thinly covered it with a layer of loctite gasket shellac sealer. I don't even use silicone on the waterpump gaskets. Silicone is a very good radiator blocker found out the hard way, let alone on the carby base, (maby I used too much of the stuff) put the carburettor back on and aligned it properly wit the crc, retightened the carby with crushwashers, very carefully.

    The difference was immediate! MUCH smoother running although the big brass screw is not seating properly aswell, but that will be dealt with as soon as I can get the carby properly milled.

    It is not worth it to do a quick fix, aspecially with a bvh's carby.

    My dad said he knows exactly what to do with the seating of the brass screw. He won't tell me what exactly but he said it can be done without too much trouble. But he will do it only after the base was fixed.

    I need to use this car so I hope this "fix" will at least hold for a week. By next week the other one will be here, that is to say the other carby's base is still fine:banghead:

    I will keep you updated on the progress, I will be heading to the big cities soon so the the carby will be off to some specialists.

    Cheers
    Corne

    Sent from my GT-I9300 using aussiefrogs mobile app
    1968 ID21 break
    1971 DS21 IE BVH Rouge de grenade (Madamoiselle Rouge)
    1974 DS Pallas Sable metalisse My first restoration (Edith) Now BVH
    1973 DS pallas Metallic red. "Rusty"

    1947 Traction Avant

    Modern

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    VIP Sponsor richo's Avatar
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    Quote Originally Posted by denxm View Post
    as michael caine would say, not many know that, .. never heard of a flector..
    It's BVH speak. Owning a D Seris Citroen BVH is like speaking in tongues sometimes, but owners of BVH equipped cars should know what I'm on about. Seek it's meaning and use in the workshop manuals, or the OED if you own a copy.
    Or buy a BVH equipped DS
    Last edited by richo; 10th May 2013 at 09:09 PM.

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    VIP Sponsor richo's Avatar
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    Re the carby, yes it will work fine.
    The 21s have the same carby, so no worries. Your fix should work at least a week, though a shellac based sealer would (I imagine) be non flexible. Fingers crossed it works for you, I'm not familiar with the product ( which means bugger all!) or its intended application.
    Anyone with a mill wo is able to accurately hold and set up can do the job.
    Your dad's correct, easy job, but it is best not to give all the secrets away. This stuff is hard won at times

    Mercedes Benz have a repair kit for their composite radiators which use an acetic acid based silicone for repairing leakage between the upper core and the top tank. I bought a new radiator instead, so I appreciate what you're saying.

    Keep up the good work Corne.
    Last edited by richo; 10th May 2013 at 09:18 PM.

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    Quote Originally Posted by richo View Post
    Roger, the unit was produced with a flat base. It needs to be milled, it is useless otherwise.

    Do not use silicone anywhere in or near an engine where it can be ingested or otherwise be caught in the engine. Bad Roger

    It's like the old saying, if it's got t*ts or wheels it will cost money. Well, silicone ingested by either has proven over time to be a disaster!
    Contact with petrol of cured RTV silicone will cause it to soften and collapse.
    roger

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    Quote Originally Posted by lhs2.1 View Post
    Contact with petrol of cured RTV silicone will cause it to soften and collapse.
    roger
    good roger

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    Fellow Frogger! CorneSoutAfrica's Avatar
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    Hi everyone

    Well finally I got to the warped base of my BVH's carburettor. My dad got a clever idea so instead of goin to the city and hope to get tomeone to help me we did it locally ons a CNC milling machine.

    To get the base perfectly flat we had to take off .7 of a millimeter. So now the base is as flat as it can possibly be.

    Next I am busy with the big brass idling screw seat which also warped with the base. I am busy lapping it slightly. Next goin to check for airleaks. I guess a bit of petrol will seep throug if there is any air leaks.

    Tomorrow the carby will go back then hopefully she wil behave more.... ladylike

    Ofcourse I will be extra careful when I tighten the nuts. Don't want to repeat the excersize again:banghead:

    I will keep you all updated with the results

    Cheers
    Corne
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    Attached Thumbnails Attached Thumbnails BVH carburettor base warped-1372103859471.jpg   BVH carburettor base warped-1372103877972.jpg   BVH carburettor base warped-1372103899038.jpg   BVH carburettor base warped-1372103919020.jpg  
    1968 ID21 break
    1971 DS21 IE BVH Rouge de grenade (Madamoiselle Rouge)
    1974 DS Pallas Sable metalisse My first restoration (Edith) Now BVH
    1973 DS pallas Metallic red. "Rusty"

    1947 Traction Avant

    Modern

    2006 C4 VTS 180 Coupe

    What would life be if we had no courage to attempt anything?
    - Vincent van Gogh

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    VIP Sponsor richo's Avatar
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    No milling machine, yet you come up with a CNC mill? Corne, you crack me up.

    0.7mm is fine. If you don't have success with lapping the idle screw (though you should) might be beneficial to begin with another carburetor. Be certain to set the CRC, if you don't already have a locking pin inserted when the carby was removed.

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    Fellow Frogger! CorneSoutAfrica's Avatar
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    Richo

    Haha yes I know, I didn't want to use that CNC mill because the machine is at my dad's work, and I do not like to ask him do it but he insisted, guess it is the best route to take. I recently aquired a BVH Safari that I should either wreck or restore, I know in the end I will restore the car, a BVH Safari is kind of a difficult to find configuration of a D. I thought of using that carby.

    This carby recently got rebushed so I would like to save this carby, at least for a few years, I had a look for another carby, saw a new unit with a pricetag of 500 euros. I am sorry I can't afford it.

    I haven't yet had time to lap the seat but after work that's the first thing I am going to do. I am excited to say the least haha, I hope my excitement is not for nothing!

    I didn't lock the crc, I actually forgot about it Will insert the locking pin before refitting. Another problem (been there a long time) my brake switch is leaking, confirmed it with my testing equipment, as if the LHM drip directly under the drivers footwell was no indication of imminent disaster. At least no rust will form there from now on. The "new" brake unit comes from a wrecked car so I hope it will be in a better condition. One day when I am big and strong and rich I can get a properly recon unit from Europe.

    In a short while I can go home and get the carby fitted.

    Will keep you posted

    Cheers
    Corne
    1968 ID21 break
    1971 DS21 IE BVH Rouge de grenade (Madamoiselle Rouge)
    1974 DS Pallas Sable metalisse My first restoration (Edith) Now BVH
    1973 DS pallas Metallic red. "Rusty"

    1947 Traction Avant

    Modern

    2006 C4 VTS 180 Coupe

    What would life be if we had no courage to attempt anything?
    - Vincent van Gogh

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    Fellow Frogger! CorneSoutAfrica's Avatar
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    Carburettor is back on, finally!! The car is much smoother but not the way I want the car, I verified my jets with the orinigal specs. All the jets seems to be the same but the primary butterfly's main jet is a 155 and according to the manual it should be a 130 I think and my secondary is 160, which should be 170 if I remember correctly.

    I am heading to my other safari which is in another town to go fetch the carburettor and take use that carby's jets. We are having alot of trouble with sourcing jets. I wonder if there is an overseas supplier who can help with different size jets? I do not want to play around with the jets too much but there must be a way to get my car to run perfectly smooth, aspecially with the BVH system it is nessecary to have a smooth idling. My idling jets are 50 on the primary and 70 on the secondary.

    Going to change my main jets and report back

    Cheers
    Corne
    1968 ID21 break
    1971 DS21 IE BVH Rouge de grenade (Madamoiselle Rouge)
    1974 DS Pallas Sable metalisse My first restoration (Edith) Now BVH
    1973 DS pallas Metallic red. "Rusty"

    1947 Traction Avant

    Modern

    2006 C4 VTS 180 Coupe

    What would life be if we had no courage to attempt anything?
    - Vincent van Gogh

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    Fellow Frogger! mberry's Avatar
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    blighmey!

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    Corne,

    If a 2.2 liter engine in decent shape with factory exhaust and intake the following is what should be there:

    Main jets 1.30 1.75
    Secondary 0.50 0.70
    Air Correction 1.55 1.55 could also be stamped AB - though may have some other designation on them as well
    Emulsion tube F16 F16

    Those are the parts you can change - and the ones most often 'screwed with'. One other note - there should be the two following numbers embossed on the bulkhead side of the carb as mounted - 23 and 27. Denote the actual size of the venturi openings inside the carb body.

    Steve

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    Default Jets !!

    Quote Originally Posted by CorneSoutAfrica View Post
    Carburettor is back on, finally!! The car is much smoother but not the way I want the car, I verified my jets with the orinigal specs. All the jets seems to be the same but the primary butterfly's main jet is a 155 and according to the manual it should be a 130 I think and my secondary is 160, which should be 170 if I remember correctly.

    I am heading to my other safari which is in another town to go fetch the carburettor and take use that carby's jets. We are having alot of trouble with sourcing jets. I wonder if there is an overseas supplier who can help with different size jets? I do not want to play around with the jets too much but there must be a way to get my car to run perfectly smooth, aspecially with the BVH system it is nessecary to have a smooth idling. My idling jets are 50 on the primary and 70 on the secondary.
    Going to change my main jets and report back
    Cheers Corne
    Hi Corne
    Would this help for some jets.
    Solex Carburetors Main Jets | eBay

    Remember the jet size in these is the hole size in mm. eg 155 = 1.55mm. I have a set of small metric drills so I have adjusted some jets over the years to rejet cars. You just use a finger operated 'pin vice' to do the drilling, no machine required.

    You should also check the jets for correct size as people have been known to do awfull things to them in some mistaken attempt to fix some problem. A set of number and letter drills can be used too but have some odd gaps in the sizes at some points.

    jaahn

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    Fellow Frogger! CorneSoutAfrica's Avatar
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    Thanks for the reply eveyone!!

    I swapped my carby's 1.55 and 1.60 for the 1.30 and 1.75.

    My car is definitely running smoother and not nearly as rich as before but I'm not satisfied.... I can't get a smooth low idling speed.

    Steve. I actually forgot something very important. The head on my car has been gasflowed and the cam was also slightly changed but it is not truely a mild cam though. Apart from that intake manifold is standard but the exhaust pipes are not the orinigal ,I think , 32mm pipes but are 40 mm pipes(stainless exhaust system).

    Jhaan thanks for the link and jet sizes. I was worried about the same thing guess the only way to know for sure is to measure them. Going to a friend this weekend with my car I think he got that drill size bits, will measure each jet and make sure what is the sizes.

    Thanks
    Corne



    Via the aussiefrogs App
    1968 ID21 break
    1971 DS21 IE BVH Rouge de grenade (Madamoiselle Rouge)
    1974 DS Pallas Sable metalisse My first restoration (Edith) Now BVH
    1973 DS pallas Metallic red. "Rusty"

    1947 Traction Avant

    Modern

    2006 C4 VTS 180 Coupe

    What would life be if we had no courage to attempt anything?
    - Vincent van Gogh

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    Hello, do you have access to a rolling road dynamometer? Fairly common in the UK. I put my DSuper5 on the rollers and let the man fiddle with jets and screws and the dizzy. Made a very noticeable improvement. Showing an indicated 70mph, Pete Balwin dived in, fiddling with the dizzy whilst looking at the power output, deafening and good fun.

    You could be messing about for ages. Only trouble with drilling them is that they always drill oversize and you can't make them smaller....

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    Actually you can if very careful. Requires a jig and sturdy drill press (milling machine better). Just fill in the opening using Ag brazing wire of small diameter. Due to the realative low temperature that Ag brazing wire melts at you can do this with a good propane torch. Then re drill the jet using a suitable holding jig and the milling machine or good quality drill press. The real trick is getting the hole exactly centered and straight as well as back drilling the jet so the hole is the proper length. Requires a bit of measuring before starting.

    Steve

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