Home › Forums › MGTD Kit Cars › VW Based Kits › Emma needs a new Carburetor
- This topic has 56 replies, 8 voices, and was last updated 8 years, 3 months ago by HappyJack.
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July 28, 2016 at 8:48 pm #301204
Hey Folks,
I’m just now getting around to dealing with some issues I had way back at Carlisle in May — namely:
- getting the driver’s side windshield wiper to stay on the shaft (had to drive from Carlisle to the hotel on the PA Turnpike — don’t ask — with no wipers in a hefty rain storm…)
- Dealing with why the engine temp went up to 220 or so on the above-mentioned 9 mile 70 MPH turnpike trip and
- Dealing with sticky throttle cable and lack of comfort with my Bug Spray center-mount carb a.k.a. FrankenCarb mounted on a make-shift center mount intake-manifold-married-to-a-dual-port-intake-manifold via pipes and clamps and bushings and prayer……..
The 1st one was an easy fix — I just had to spend lots of $$ at MGMAGIC for new wiper fittings.
#2 may be due to that pesky Bug Spray Carb setup — or maybe my insistence on fitting the stock deflector fins and thermostat to the fan shroud when we rebuilt the engine last November…..not sure that the fins are opening as they should —
#3 was going to get fixed by installing a pair of Kadron 40mm carbs onto a pair of intake manifolds, adding some linkage and voila — I’d be as happy as Schu is with the Kadrons he has been running for the past 10 years or so on his TDr.
But those are hard to find used and are a bit pricy new — there is one source in CA — The KADDY Shack, that specializes in reworking and re-jetting new Brazilian Kadrons for the Dune Buggy crowd — I was all set to PayPal them hundreds of dollars when I found a center mount, made in Spain, Weber 40IDF carb and center mound manifold on eBay for $94
So instead of dual Kadrons, I am going to try the center-mount weber. Anyone have experience — good or bad — with using an IDF 40 Weber center-mount carb on a Tdr?
Worst case, if this iteration of “find the best carb for Emma” does not work out, I can try to find another reasonably priced Weber, a set of intake manifolds, a center-pull linkage kit, and go with dual Webers — or do as Shu did and go with a set of Kadrons.
The Weber is due to arrive this Monday. In anticipation, I purchased a repair kit for the carb and a 1 gal “Dip Tank” Carb cleaning kit. Once I get the Weber it will get carried over to Royal’s shop to be stripped, dunked, reassembled, and installed — that’s the plan and it should work provided that $94 Weber is “rebuildable.” It seems that Royal is a bit of an expert on rebuilding carburetors and has volunteered to help — and he lives 5 miles away from me — stay tuned!!
I had planned on inserting some before pictures of the Bug Spray Carb mounted on Emma but I can’t figure out how to insert a picture so the BEFORE shot of the Bug Spray is posted in my Media center under Happy Jack. There is also a picture of the carb-cleaning dipping tank for your viewing pleasure and comments.
Comments?
Suggestions?
Ideas?
Therapy Recommendations?
Thanks, Happy Jack
July 28, 2016 at 9:15 pm #301205“a bit of an expert on rebuilding carburetors”?? Hardly! (It’s all sleight of hand.)
July 29, 2016 at 2:13 am #301212Jack, I have two responses that may or may not be helpful.
You said your engine temperature went up to 220. My own engine temperature almost always goes to at least 210 and frequently hits 220. That’s mostly stop and go driving in Las Vegas, where we’ve been 110 degrees or more for a couple of weeks now, and that may make a difference. Regardless, I was concerned enough to ask my “new” VW mechanic, and he tells me not to worry unless it hits 230 and stays there.
You also asked about using the Weber progressive carburetor. I have such a carburetor on my car. It starts easily and runs enthusiastically, but I still wouldn’t recommend it for several reasons. First, it’s a PITA to adjust. Just google that. Hard to reach the adjustments and hard to get the adjustments right. Second, it seems to be cold-blooded, meaning that until it’s warmed up, it has flat spots and hesitates a lot — after warming up, however, it runs just fine. In Las Vegas, this is not a problem — in your neck of the woods, maybe it is. Third, what is DOES do is give great acceleration (relatively speaking) when that second barrel opens up. With the gearing on my car, it’s not a problem but neither is it necessary. Last and most important, it sure seems to be a (*&^% gas hog! My gas gauge doesn’t work very well, but it sure does seem like this thing sucks down gas like a 4×4 SUV, especially when I put your foot down which apparently is pretty often (I don’t even notice doing it, but I get great gas mileage in my other cars and this one gulps gas). As little as I drive, it’s almost an inconsequential complaint, except that the tank itself isn’t very large and so frequent gas stops are required lest I run out.
In hindsight, I wish I had stuck with the plain old VW carburetor. They also say that dual carbs are not cold-blooded and are also very efficient because they have such a short route to the cylinders. I wouldn’t get two-barrel dual carbs, however, unless you like to suck down gas.
- This reply was modified 8 years, 4 months ago by John Simion.
July 29, 2016 at 11:22 am #301234I have always had trouble keeping my engine temperature under 210 unless I limit my speed to 55mph.. This year I built myself an “oxyboxer” to install and got it all running thinking that with twice as much oil it surely would run cooler! No such luck! I almost wish I didn’t have a oil temperature guage! I have resigned myself to driving the car without looking at the guage as much as possible. BTW I have dual weber ict’s on mine, no flat spots and pretty acceptable warmup driving. runs real good once warmed up. The engine is 1600 dual port with aluminum bottom end from 1.9 vanagon
July 29, 2016 at 12:06 pm #301238Hey Eddy & John,
I know what you mean about wishing you did not have a temp gauge installed — ignorance is bliss — for a while at least….and I don’t even live in the “hot” part of the country like you folks in Las Vegas and beyond (although is is 97 in the shade here today in Coastal North Carolina).
I’ve read a lot (mostly warnings) about using a single Weber 2 barrel 40 ICT on a small (1641) engine…we shall see….I’ll post the results once I get the carb sorted out and installed.
Happy Jack
July 29, 2016 at 12:21 pm #301240As devil’s advocate here… if you are running a VW engine WITHOUT the “doghouse” oil cooler, your oil temp and engine will be about 10-15 degrees hotter due to the lack of sufficient cooling air to the #3 cylinder.
Allen Caron
VW based 53MGTD - "MoneyPenny"
"If one thing matters, everything matters" - from the book The ShackJuly 29, 2016 at 3:36 pm #301244Good point Allen — I do have a doghouse cooler on this engine — so the engine temp should be more stable and even. I also have a #3 cylinder temperature monitor so I can tell how hot #3 is and then extrapolate from that how the whole engine is doing heat wise. That monitoring setup is leftover from when I had the 2332cc engine in the car, but like Eddy stated, sometime too many gauges are not a good thing.
— Once I get the new Carb in hand and ready to install, I plan on puling the fan shroud and checking the vanes and thermostat — and will take the advice of my local VW expert Dalton and “take those stinking’ vanes and troublesome thermostat out and throw it all away” I’ll also have to change the air intake path with the new Weber (filter on top of the Carb) — Between these two changes I hope to cure the “runs hot” problem — we shall see —
Jack
July 29, 2016 at 5:50 pm #301246My 2 cents:
1. The single 40 IDF will likely require a lot of tweaking to get running satisfactorily. You are still facing the issue of no heat-risers on a center-mount carb with unequal (and long) distances from the carb to the heads. But, that IDF is far, far more tunable than the Bug Spray. Suggest you “study up” on the transition circuits and the impact of jet changes and emulsion tubes. The challenge with your small/mild engine is that you’ll likely have to tune it relatively lean at low RPMs, and most of your driving will be done on the transition circuits. Spend the $$ for the Weber Tuning Manual.
2. I’ll confess that your local VW “expert” discussing removing the vanes and thermostat sends up a huge “red flag” to me. They are there for a reason (actually several) and if VW could’ve saved money OR improved reliability by removing “unnecessary” parts, they certainly would have. Second, controlling the warm-up on your engine without heat risers is exactly what you need to prevent bogging and stumbling during acceleration — especially since you have no choke. If you’re concerned that airflow is somehow restricted, causing higher temps, it’s easily checked. Make sure the spring on the back of the shroud is there, and then remove the thermostat. That spring should hold the vanes wide open internally, and you can drive it that way, with the thermostat removed. It will have similar effects as running a water cooled engine with no thermostat. Note that you can adjust how far the thermostat closes by turning it on the linkage rod, but can’t really adjust how far it opens – it will expand/extend based on its design.
My 2 cents…
Early FF TDr on 69 VW pan
Slowly coming back from the ashes...July 29, 2016 at 8:55 pm #301252Hey Kentt —
I appreciate your 2 cents — I’ll check out the spring, the vanes and the thermostat — and take your advice about leaving that system intact….
As to the center mount, the intake manifold that is included with the Weber has provisions for the heat risers — but apparently they were misplaced some years before and were not in the post on eBay. I’ll know for sure if I have to try to find or make some replacement heat risers once I get the package on Monday. So i’ll be putting the heat risers in and leaving the engine warm up vanes and thermostat in place. No sense starting out in the hole especially if getting that Weber set up to run properly will be such a “fun” project….
On another but similar note, what do you think about adding velocity stacks to the Weber? In looking at the various sites, the IDF 40 does not ship with velocity stacks, but they are sold as add-ons — the 44’s and 48’s do ship with velocity stacks installed. Would velocity stacks be useful in this center mount application?
Happy Jack
July 29, 2016 at 9:21 pm #301254Sorry to hear of your trouble, Jack.
I add my endorsement to the idea of not removing the thermostat and air vanes. Thing to do with those is tinker with them until they work right.
I doubt that your carb is what made your temp go up. Unless the carb was leaning you out at 70 mph, yout temp went up because of an air flow issue. Look for that.
As for the sticky throttle cable, I would not try to fix that by rebuilding another carb—unless I had already narrowed the “stick” down to a wowed-out butterfly shaft or something similar. And even then…I’d be looking for a carbaloid or bronze bushing for that malady.
Good luck to you and Roy both!
July 29, 2016 at 9:37 pm #301258Ed, surely you know that these aren’t really problems…..only challenges. Something to have fun with and keep us out of the bars. 🙂
July 29, 2016 at 9:45 pm #301261Hey Ed,
The issue with the throttle cable has to do with the route the cable has to take to reach the BugSpray Carb. We had to chop down the intake manifold to get it to fit under the engine cover on the BCW — which forced us to re-route the throttle cable into the left side of the engine compartment and then take a sharp bend to reach the carb linkage — had to use an ATV hand throttle cable to extend the throttle cable enough to make the hook up. I have a new respect for the simple route that the throttle cable takes from the gas pedal to the carb in a “normal” VW engine setup!!
Plus I just want to play with installing the Weber to see if I can regain some of the “goosieness” I got from the dual Dellorto DRLA 45’s on Emma’s previous engine….
Plus I have to keep up with the guy who decided to power his BCW Tdr with a fine Japanese engine as a winter project last year….!!!
Happy Jack
July 29, 2016 at 9:51 pm #301262The reason that we had such a Rube Goldberg fix on the linkage of Jack’s Holley BugSpray was because of interference with the alternator. I had no problems at all with my “old school” generator.
July 29, 2016 at 11:31 pm #301282If you can get heat risers working on your intake, I suggest you do so before you start trying to tune your carb. If you are running an aftermarket exhaust, make sure it has the holes drilled out to allow that heat flow to occur – most do, but I’ve seen some that don’t, requiring me to drill/ream the hole out.
I like velocity stacks, they contain the fuel/air mix standoff, and IMO provide better/smoother throttle response throughout the RPM range. On high performance engines they make a measurable difference, and you can actually tweak where that difference occurs in the RPM range with different height/lengths of stacks. Factory VW air cleaners had a velocity stack built into their shape that was about 4″ tall or so. You likely won’t have enough hood clearance for tall ones – but I have 1.5″ ones that fit inside the 3″ tall air cleaners on my dual 36s. They likely don’t make much power difference but they have the side benefit of making it easier to use my carb synchronizer while keeping the standoff contained.
The reason you’re likely to have a bit of a tuning challenge is that with a large carb/small displacement combo, you’ll likely be running on the idle and transition circuits for about the bottom 3/4 of your throttle travel. You’ll only be using the primary jets for full throttle operation – that’s a bit of an overstatement, but it should communicate. Your normal driving will be done on those transition circuits which is both a blessing and a curse. More complicated to tune – but should allow you to tune out any hesitation or stumble as you accelerate off idle.
Early FF TDr on 69 VW pan
Slowly coming back from the ashes...July 30, 2016 at 1:32 am #301284I installed a fan housing and fan from a 1975 fuel injected engine today. this housing has the “vortex ring” or what ever they call it! It is also made a little different so doesn’t require the “hoover bit”. I highly recommend it! appears to have reduced my temps by at least 10 degrees. even at 75 miles per hour I didn’t go over 210 degrees and ran comfortably at 190 driving at 60 mph. car will go over 85 mph and feels as steady as a rock but the fence posts are going by to fast for my liking over 60-65! LOL
July 30, 2016 at 9:23 am #301294Eddy, that addition of larger fan and the vortex ring on the new shroud likely increased your cooling air flow at least 20%, perhaps as much as 25%. Good move, IMO!
Early FF TDr on 69 VW pan
Slowly coming back from the ashes...July 30, 2016 at 9:28 am #301295I already had a large fan (aftermarket) and a doghouse shroud, so this was an upgrade to the FI shroud and a volkswagen fan.
July 30, 2016 at 9:52 am #301298FYI – You can buy a venturi ring and install it on earlier shrouds. I’m running a Scat doghouse shroud (with heater tubes), the larger VW fan, and installed one of those venturi rings on it. It provides a similar function as a carb velocity stack – it smoothes out the airflow at higher RPMs since the air no longer has to travel around a 90 degree corner to enter the fan.
Early FF TDr on 69 VW pan
Slowly coming back from the ashes...July 30, 2016 at 11:36 am #301301I had a scat doghouse shroud on my oxyboxer with a type 4 oil cooler. I used it to get better clearance for my dual weber ict carbs. it didn’t cool nearly as well as the fi shroud does with just the type 1 oil cooler. it didn’t have the venturi ring on it though and it also had an aftermarket fan in it. I think the VW guys are right though, the engine needs the thermostat vanes in the shroud to properly direct the cooling air to the heads. my scat shroud doesn’t have the vanes. This engine is a watercooled vanagan engine that I removed the water jackets from and adapted it to accept the aircooled cylinders and heads. I used original vw 1600 cylinders and dp fuel injection heads. This gets me an aluminum block with oil filter, a stronger crankshaft, larger oil capacity, hydraulic lifters and a 5 bolt flywheel attachment rather than one gland bolt. I thought it would run cooler because of the increased oil capacity but I guess the aluminum block doesn’t dissipate heat as well as the magnesium one does. I have it running great now
July 30, 2016 at 11:42 am #301302By the way, I recommend the dual ict’s over any single carb on stock or nearly stock volkswagens. My engine never ran so good and there is no concern about getting heat to the carb like there is on centermounts. most heat tubes on Volkswagens are long since plugged with carbon anyway and those long runners are way to cold for the fuel to stay atomized till it gets to the cylinders.
July 30, 2016 at 11:52 am #301303I would like to try a manifold like this one though!http://www.headflowmasters.com/the-cheater-single-carburetor-vw-manifold.html#.V5zMrhOgBPY I think it would need some kind of heat to be a good runner from cold engine to hot though!
July 30, 2016 at 12:00 pm #301304That center mount would give individual, equal length runners for a 48 IDA – but would not allow you to use a factory alternator/generator stand nor shroud. I’m not sure what it’s application would be, other than drag racing…
I modified my Scat shroud to add the vanes, thermostat and Hoover bit.
Early FF TDr on 69 VW pan
Slowly coming back from the ashes...July 30, 2016 at 12:18 pm #301305a problem with dual single throat carbs is that the number 1 and number 3 cylinders run lean at idle because of the intake timing. the timing is more even if 1 and 3 are on a common throat and 2 and 4 on another. also a single two barrel is considered easier to synchronize than two individual carbs two feet apart! The crossfire manifold does allow the stock alternator and stand.
August 2, 2016 at 10:28 pm #301347I got my center mount Weber carb and manifold today and it looks pretty good. With Roy’s help, I dismantled it and put the various parts in the dunk tank of carb cleaner and let the parts soak while I removed the Bugspray Carb and manifold from the car. In the process I found that the intake manifold nuts had loosened up on the driver’s side, probably causing a vacuum leak and thus probably causing a leaning out of #3 and #4 cylinders and causing hotter than normal running temps???
In reading posts on The Samba, it seems like after-market metal intake manifold gaskets are being blamed for the intake manifold nuts loosening up over time…the posts suggest using fiber gaskets vice metal ones, or if you have to use the metal ones, treating them as “One Time Use Only” and replacing them anytime an intake manifold is removed and reinstalled.
So my order sheet now includes new fiber gaskets, new copper lock nuts for the intake manifolds and last but not least, a Venturi Ring for my fan shroud as suggested by Eddy and Kentt–
Stay tuned for the next chapter in my “Emma Needs a new Carb ” saga — which may also inadvertently solve my hot running engine problem!!
Happy Jack
August 3, 2016 at 4:57 am #301348One of the fitment surprises we are having is because the prior owner (used manifold) had shortened the legs where it mates up to the rubber/neoprene boots and end pieces. Unfortunately, my son in Virginia Beach, has my MIG welder. We need about 1/2″ longer on each side to be comfortable. Any ideas, short of taking to a welder??
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