Author Topic: Automatic Transmission question  (Read 1673 times)

Bonnyboy

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Automatic Transmission question
« on: September 13, 2020, 04:20:58 »
A neighbour had a visitor with a 230sl last week that I got the opportunity to drive.  Its an automatic and I have never driven an automatic before but I have a few questions - are they all like this?

1.  car revs high in park and when I put it in #2 the car lurched forward and I had to tromp on the brake to keep from rear ending my car - same at a light where I had to have lots of pressure on brake or it would drive through intersection with my foot off gas.

2.  when I put the car in Park there was a loud crunching noise from rear end - is there a splined shaft that could be broken?

3.  the car was very anemic as in absolutely gutless. Compared to my 280sl this thing was a slug in town - I was afraid to take it on the highway.  Sounded like a brake shoe was rubbing

4.  it was hard to start cold and I noticed that one of the two wires on the cold start valve was not connected - it looked intentionall left off - is there a reason the mechanic would do this or is it just sloppy work?

5. The trunk and hood seemed much lighter than on my car when I opened and closed them - were they lighter on the 230sl or do I just have several coats of paint on mine that would add to weight? 

I gave him the address of this site and suggested he become a full member and then to take the car to a shop that knows what they are doing because I didn't think it was safe as is. 

Any suggestions? 

Am I over reacting thinking that the car shouldn't lurch forward when going in gear or are the automatics like this.      I have been toying with the idea of getting an automatic due to my sciatic issues but if they are all like this I'll stick with my 4 speed and just deal with the pain when I push in the clutch. 

Any recommended pagoda savy mechanics in Vancouver BC I could give him the name of - Milo??

Ian
69 280SL
65 F-100
73 CB750K
75 MGB
78 FLH
82 CB750SC
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JamesL

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Re: Automatic Transmission question
« Reply #1 on: September 13, 2020, 09:09:51 »
That crunching to P is not right
Mine's an auto and barely creeps forward when in gear.

That said.... isn't #2 where the gearbox "max" gear sits, so 2 has a 1st gear (tree-stump pulling)  in play when stopped? I can't recall ever sticking mine in 2 and testing any "creep" (or worse). I leave mine in 4 and let the gearbox do it's thing, which is a 2nd gear start when stopped. Unless I am on twisty/hilly bits when I'll move between #3 and #4

Tech manual: "When in normal driving position "4", and starting off, the Pagoda starts in second gear. First gear is only selected when the gear lever is put in "2", and then drive off from standstill. " So MAYBE that "lurch" is normal ?

 
James L
Oct69 RHD 280 in DB906 with cognac leather

Pawel66

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Re: Automatic Transmission question
« Reply #2 on: September 13, 2020, 09:25:04 »
I do not have much experience with driving 230SL, I have an automatic 280SL. Therefore difficult to comment on how heavy or dynamic 230SL is.

But I think that any of your points 1 and 2 that relate to auto transmission performance are not typical. I think the transmission you tested is out of tune. I also think that the engine is out of tune as well - which would result with transmission not working properly.

My experience with my auto transmission is - it works very similar (in feel) to modern transmissions. You select 4, the car starts advancing very slowly, gear shifts are smooth, no clunks on deceleration. Yes, there is slight clunk and slight rev increase when you hold the brake and select P. Yes, it has the tendency to start faster when you select R. But this is all. As long as engine and transmission are in tune. The engine needs to be in tune, particularly idle, t oproduce correct vacuum, then the transmission 3way solenoid needs to engage properly, meaning the throttle switch needs to be set properly. Finally, the transmission pressure needs to be set properly.

As JamesL said, you normally start with 4 selected. Then the car starts from gear 2. If you select 2, the start is from 1 - for sporting occasions, maybe steep hills - I never used it, actually. I can imagine starting with gear 1, when the car is out of tune might have felt like you cannot stop it as if the brake booster was shot. But this is not typical condition.
Pawel

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JamesL

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Re: Automatic Transmission question
« Reply #3 on: September 13, 2020, 16:40:44 »
I drove mine today and put it in 2 to try a few starts/let foot off the gas. No lurching whatsoever. So I think Pawel is right - something wrong with the set up of the tranny or engine or both.
James L
Oct69 RHD 280 in DB906 with cognac leather

stickandrudderman

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Re: Automatic Transmission question
« Reply #4 on: September 13, 2020, 18:10:56 »
There are so many idiosyncrasies to these cars; if they're not properly set up then the symptoms you describe are just some of the ways that many faults can manifest themselves. That's why it's important to engage a knowledgeable technician to oversee any purchase or maintenance.

Bonnyboy

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Re: Automatic Transmission question
« Reply #5 on: September 14, 2020, 04:52:57 »
I stand corrected -  I did put it in #4 and I remember the owner saying it starts in 2nd gear.   Thanks for the comments -  I'll try to help him find a good mechanic. 
Ian
69 280SL
65 F-100
73 CB750K
75 MGB
78 FLH
82 CB750SC
83 VF 1100C
94 FLHTCU
08 NPS50
12 Pro 4X