| Author | Message | ||
| Pat Bartlett (Muddog16)
Rating: N/A |
I am getting ready to purchase a new Air Throttle and I have been reading some of the older threads in the archives. Evidently the signal line is 3/8", If the response is sluggish, then my theory is go to a smaller signal line going to the engine say 1/4" line instead of the 3/8" line less volumn more response, larger signal line would be more sluggish, acting like a dampner or accumulator. If that is the proper description. I'm just kicking this around when I brought the bus home at times I'm sure I stood up on the gas pedal, maybe its just the old race car driver in me! But down the line I'm sure that cruise is an option! Ok lets here pro's and con's, that is why I'm asking..................Pat http://prevostlemirage.blogspot.com/ | ||
| Jim & Linda Callaghan (Jimc)
Rating: N/A |
I think there is a small amount of hesitation as the air responds, but with a bus, I really dont think it matters all that much. If you are going with cruise in the future, I would think you would need air if your linkage is a stiff as you say. Jim 4106 Wisconsin | ||
| Tim Hoskinson (Tdh37514151)
Rating: N/A |
I have a air throttle on my 4104 and I don't care for it myself. I have a 1948 4151 with mechanical throttle and really have no problems with it. The air throttle is not as responsive on exceleration or deceleration. As allready stated not such a big deal as far as trying to gain or loss speed but when trying to maintain medium speeds my air throttle tends to speed up or slow down with no change to the pedal so unless you are running at govern speed it seems I am constantly fighting the pedal to maintain speed even on level ground with no varying load on the engine. In fact if you are to try and hold the engine at one particular rpm sitting still out of gear your in for a battle. At first I thought maybe its just my throttle but after checking with some of the guys our truck club others have had the same result. Of course this is only my opinion and others may not be bother by this. Choose what makes you the most comfortable. Tim | ||
| FAST FRED Rating: N/A |
For a stick transmission an air throttle is a very poor choice. They work OK with slushpumps, Stab & Steer ! FAST FRED | ||
| Geoff (Geoff)
Rating: N/A |
The air throttle has to be sluggish to a certain extent-- if it gets too responsive you would be pegging the engine rpms at the slighest overtouch. I have an air throttle in my RTS and it works great with the automatic transmission. I have heard of people using them with a stick shift and saying they had no problems, but I wouldn't do it. If you do put an air throttle, it is very easy to install a Rostra cruise control at the pedal. --Geoff '82 RTS AZ | ||
| David Evans (Dmd)
Rating: N/A |
Tim, do you have a auto or manual with the air throttle? | ||
| Tim Hoskinson (Tdh37514151)
Rating: N/A |
David my 4104 still has the four speed manual trans and 671 inline engine. The previous owner had the air throttle installed. It works ok out on the open high way with stock drive trane to run 65 mph you push it to floor lay your foot on it and let the gov. be your cruse control . I can see were the air wood work ok on a auto trans. but on the manual I personally wood not change one to air if the mechanical was working ok. Tim | ||
| Donald Lee Schwanke (Dontx)
Rating: N/A |
The later GMC4905 standard transmissions came with an air throttle, GMC made a bunch of em, I found no problems with it on a clutch setup, loved it in fact. GMC made a lot of them that way and I never heard of anyone changing back to a cable or disliking it. In converting one to air throttle, you can get all kinds of leverage options, maybe that is why some dislike it, maybe made it too sensitive or such. | ||
| Frank71 Rating: N/A |
fix the one thats on there, i had air throttle put on mine when they put the automatic in it, i cant see any advantage to doing this, my old one worked just fine, properly maintained Frank allen 4106 | ||
| Gary Stadler (Boogiethecat)
Rating: N/A |
My old Superior pusher had an air throttle and a stick and it was just fine. I never had a complaint about it. I'd have one anytime.... | ||
| t gojenola
Rating: N/A |
I recall this discussion some years ago when it was pointed out that air throttle setups supplied for the transit industry were deliberately designed to produce a slower response. This was one of those things mandated by the EPA to reduce emissions and/or particulates from diesel engines. The Williams catalog has completely separate components designed for "Off Hiway use only.." Also, an air throttle used in conjunction with an automatic transmission requires an air modulator - which, if you look at the Williams catalog, requires a 75PSI limiting regulator in the supply. With a standard transmission, one could conceivably supply it with full air pressure. If you are buying a new system for use with a manual transmission, i'd suggest you discuss these issues with one of their engineeers or sales reps. I have a transit-donor air throttle and modulator on my 4106 with V730, and could not be happier with it. I have the supply regulator set at 65psi and the air lines are 1/4". I also have a dual air gage with the auxiliary pressure reading the pressure supplied by the accelerator pedal. It will almost instantly jump to full pressure, but the engine response is delayed. I suspect the speed could be improved by changing or altering the slave cyllinder. Maybe it has a restricting orifice? hth tg | ||
| Pat Bartlett (Muddog16)
Rating: N/A |
Excellant Tg, that is what I was wanting to hear, I know that a smaller line will improve the signal, a larger line by volumn alone will allow it to act like a snubber or dampner. The possibility of a restricting orific. Not knowing what the signal air pressure doesn't help me either. But you mentioned a Williams catalogue  that is interesting, I'm going to run a google and see what I can come up with! Pat | ||
| t gojenola
Rating: N/A |
http://www.wmco.com/products/throttle_controls_catalog.pdf tg | ||
| Matt P. Rating: N/A |
I had a transit with an air pedal. It worked good after the air pressure came up. I could not rev up the engine to build pressure faster so it took more time to get going from a stop. If your bus has no air leaks than this is not a problem. However, you do not see many old buses without air leaks. | ||
| Pat Bartlett (Muddog16)
Rating: N/A |
Thanks TG, I ran a goole last nite and checked out their site. I noticed that they have two types of throttle control cylinders. One uses a single line from the pedal to the throttle control cylinder and the other uses two, this one has a fast idle mode that allows the engine to warm up. Its more expensive but I would think that this is the way to go! That would also make me think that there isn't a flow orfice in the throttle control cylinder, evidently the pressure applied to the pedal is directed proportional to the signal going to the throttle control cylinder, this second line is a steady flow allowing for engine warm up. Thanks again TG the was a good site! Pat |