1
Research & Development / Re: Easy fix for a minor irritation
« Last post by Benz Dr. on Today at 07:03:05 »Stick, please post a photo next time you have a rod in your hand.
No one needs to see that.
Recent Posts
No one needs to see that.
2
W11x chassis cars / Re: How much are m129 engines worth these days?
« Last post by Heckflosse on Today at 05:00:53 »I might be looking for a good core as well; I'm in Canada though. So in line...if it's still available...
3
Drive train, fuel, suspension, steering & brakes / Re: M129 idling issues
« Last post by Heckflosse on Today at 04:49:30 »Thanks, that's what I've done, even so far as to get a vacuum manometer on them, here's what's funny; - if I blank off one of the carbs, the RPM picks up to 1500 or so. It will not run at all with the mixture screw turned in to 2 turns and the throttle plates level; - it will only run when on the power circuit.
Even with the valve lash set properly, there's a lot of spitting out the back end, and it sounds like multiple cylinders. And it will spit back out the rear carb at 1000 rpm every minute or so as the fuel builds up.
A little background; the car ran well enough when I got it, and so I put some new plugs in it, did an oil change, overhauled the carbs to try and take care of a hesitation issue, and then scoped it. Compression at that time was 10 lbs more across the board, vacuum at idle was low, about 12. Then it ran beautifully, and I thought I got the problem solved. Well, it didn't take 2 hours, and then it wouldn't accelerate, it would backfire out the exhaust violently and spit back through the carbs under load, and then it refused to idle. And that's where it's still at. I should note that the carbs had been overhauled (by me) 3 weeks before this occurred, so it wasn't the carbs going out of whack.
So here's what I'm thinking; - the cam is wiped, the duration is a lot longer than permissible and the valves aren't opening up enough, - so at low speeds, the engine doesn't seal up enough for good compression and dies off. Excess fuel either sits in the intake as a result of next to no vacuum, and the miss I hear out the back is because the exhaust valves stay open too long don't open enough either.
Does anyone have any other possible explanation for this, yes, I agree, it sounds like it should be simple enough, and I do keep getting this feeling I'm overlooking something really simple, but I've done all the preliminary "start with a dead engine" stuff. It's not that, I have plenty of spark, I have plenty of gas, both pump and return circuit are up to par, I've checked for vacuum leaks on the manifolds, carbs and bases, and the power brake booster, and that turns up fine. The carbs themselves are good clean Zeniths from the same engine, numbers and jetting match for the 250, and the throttle plates are in good shape and not loose. Needle and seats are checked and don't leak, accelerator pumps are new and put out a full shot, the fine passages are all clean (mechanically cleaned as well as chemically) and they were perfectly set to match when I put them on.
Spark is also good and strong; - it's an electronic ignition, can't remember off hand which company it came from, it was a Dutch outfit and the distributor curve is properly set up for this engine.
So yes, it appears I'm over thinking this thing, because it was basically running acceptably one minute and then like a toilet the next, but everything I've recently read about camshaft failure is pointing to this, the misses in the exhaust, poor idle, low vacuum, and the physical damage of the lobes actually being close to a full millimetre shorter and flatter looking than the other 2 cams I have as spares.
I guess if swapping the cam out doesn't work, then the whole thing is coming apart anyway, I don't know what else to do here. I just really didn't want to have to do that now. I know that engine is on borrowed time, it was when it ran.
And since I've never swapped a cam in a Mercedes before, I was wondering what precautions, or what tricks I have to do to swap it out without destroying anything else. If this was an American car it'd be a lot more forgiving with ham-fisted mechanics than this thing seems to be.
Even with the valve lash set properly, there's a lot of spitting out the back end, and it sounds like multiple cylinders. And it will spit back out the rear carb at 1000 rpm every minute or so as the fuel builds up.
A little background; the car ran well enough when I got it, and so I put some new plugs in it, did an oil change, overhauled the carbs to try and take care of a hesitation issue, and then scoped it. Compression at that time was 10 lbs more across the board, vacuum at idle was low, about 12. Then it ran beautifully, and I thought I got the problem solved. Well, it didn't take 2 hours, and then it wouldn't accelerate, it would backfire out the exhaust violently and spit back through the carbs under load, and then it refused to idle. And that's where it's still at. I should note that the carbs had been overhauled (by me) 3 weeks before this occurred, so it wasn't the carbs going out of whack.
So here's what I'm thinking; - the cam is wiped, the duration is a lot longer than permissible and the valves aren't opening up enough, - so at low speeds, the engine doesn't seal up enough for good compression and dies off. Excess fuel either sits in the intake as a result of next to no vacuum, and the miss I hear out the back is because the exhaust valves stay open too long don't open enough either.
Does anyone have any other possible explanation for this, yes, I agree, it sounds like it should be simple enough, and I do keep getting this feeling I'm overlooking something really simple, but I've done all the preliminary "start with a dead engine" stuff. It's not that, I have plenty of spark, I have plenty of gas, both pump and return circuit are up to par, I've checked for vacuum leaks on the manifolds, carbs and bases, and the power brake booster, and that turns up fine. The carbs themselves are good clean Zeniths from the same engine, numbers and jetting match for the 250, and the throttle plates are in good shape and not loose. Needle and seats are checked and don't leak, accelerator pumps are new and put out a full shot, the fine passages are all clean (mechanically cleaned as well as chemically) and they were perfectly set to match when I put them on.
Spark is also good and strong; - it's an electronic ignition, can't remember off hand which company it came from, it was a Dutch outfit and the distributor curve is properly set up for this engine.
So yes, it appears I'm over thinking this thing, because it was basically running acceptably one minute and then like a toilet the next, but everything I've recently read about camshaft failure is pointing to this, the misses in the exhaust, poor idle, low vacuum, and the physical damage of the lobes actually being close to a full millimetre shorter and flatter looking than the other 2 cams I have as spares.
I guess if swapping the cam out doesn't work, then the whole thing is coming apart anyway, I don't know what else to do here. I just really didn't want to have to do that now. I know that engine is on borrowed time, it was when it ran.
And since I've never swapped a cam in a Mercedes before, I was wondering what precautions, or what tricks I have to do to swap it out without destroying anything else. If this was an American car it'd be a lot more forgiving with ham-fisted mechanics than this thing seems to be.
4
Body, interior, paint, chrome, and cosmetic items / Re: After Market Air Conditioning 1964 230SL
« Last post by doitwright on Today at 00:51:46 »At some point in the next month I will post a few photos and explain where things stand on the integrated A/C development. I am at a point where the major components have been fabricated and test fitted. There are still many smaller details to be worked out. They will get worked out. Just need to determine how.
I can say it this point, my design will only fit LHD vehicles. That is not to say that a system based on the same design principles could not be made, but several components would need to be a mirror image of the LHD to fit a RHD car.
I can say it this point, my design will only fit LHD vehicles. That is not to say that a system based on the same design principles could not be made, but several components would need to be a mirror image of the LHD to fit a RHD car.
5
General Discussion / Re: Concours/Resto Mod Restoration Shop
« Last post by Cees Klumper on May 22, 2024, 23:55:17 »My client choked a little bit and asked me to research a stateside shop and we don't necessarily want to do an engine swap, just modern drivability upgrades and restoration.
If your client is ok with maintaining the original (type) engine that simplifies matters considerably. As for 'drivability upgrades' a partial list would include:
- 123 ignition
- progressive rate springs
- replace all suspension rubber (and all other rubber while at it) which will transform most older Pagoda's ride characteristics for the better
- bluetooth stereo
- proper working A/C, depending on your climate
- automatic seat belts
- depending on the transmission in the car (automatic or manual), maybe a rear differential upgrade (auto) or conversion to 5 or 6 speed (lots of work, not really necessary)
A properly sorted original spec Pagoda with these additional features will drive very comfortably and will be sufficiently quick for most people.
6
Drive train, fuel, suspension, steering & brakes / Re: spark plug weirdness
« Last post by Charles 230SL on May 22, 2024, 23:42:07 »..I am guessing that the #1 injector pintle is not seating completely, or (more likely) the spray pattern is distorted by partial clogging (resulting in poor atomization which leads to incomplete combustion)..
I agree Larry, #1 is definitely a bit rich and my first suspect would be the injector. One of those injector testers/cleaners Michael mentioned would come in handy right now.
7
General Discussion / Re: Concours/Resto Mod Restoration Shop
« Last post by mdsalemi on May 22, 2024, 22:33:29 »the last i checked Gernold at SL Tech was a Mechatronic "distributor" here in the states.
i would start there if mechatronic the way the owner wants to go
Gernold brought one to one of the last PUBs in Blacklick some years ago. That's when I had the opportunity to drive it. Don't know what happened to that car, probably sold.
If time isn't too important, RamAir, go to the next SEMA/AAPEX show in November; it's only six months away. As I mentioned, there will be so many restomods there you could talk to dozens of builders/makes all in one place all in one trip and see some of their work to boot. But if the client wants to get started soon, well, that's another story.
8
Body, interior, paint, chrome, and cosmetic items / Re: Missing Chrome?
« Last post by acbrock on May 22, 2024, 22:33:22 »Ah yes when looking at the pics again. There is no other piece the one I was seeing was on the door. Looks like your Dash Piece just fits the area better than mine and it is the same on both sides. That was as low as I could get it and that was even difficult. And when I look at the original pictures the gap was there. I guess I will wrap around that join of the metal and tuck it under the crome and see if that works. But it definitely feels wrong because the screws are poking thru from the chrome piece. I think it should be covered by the dash piece. Hmm. I will search more and then maybe take the pieces of again at some point and see if they can go lower.
9
Drive train, fuel, suspension, steering & brakes / Re: spark plug weirdness
« Last post by mdsalemi on May 22, 2024, 22:28:52 »Larry, looks like an "un-uniform" look to the plugs. #1 looks to be a little fouled. #2 & #3 may be a little hot? 4,5,6 look normal unless I have it all wrong...
Maybe you should find someone with one of those injector testers and see how they all shake out!
Maybe you should find someone with one of those injector testers and see how they all shake out!
10
Drive train, fuel, suspension, steering & brakes / spark plug weirdness
« Last post by lurtch on May 22, 2024, 22:16:08 »Hello All,
I pulled the plugs after completing two 80 + mile runs through the Wine Country back roads with my touring group. This was also proof testing for the new Pertronics unit I installed.
The car ran flawlessly the both times, so I was surprised to see this going on with #1 plug.
I am guessing that the #1 injector pintle is not seating completely, or (more likely) the spray pattern is distorted by partial clogging. ( resulting in poor atomization which leads to incomplete combustion ).
Anybody care to weight in on this?
Larry in CA
I pulled the plugs after completing two 80 + mile runs through the Wine Country back roads with my touring group. This was also proof testing for the new Pertronics unit I installed.
The car ran flawlessly the both times, so I was surprised to see this going on with #1 plug.
I am guessing that the #1 injector pintle is not seating completely, or (more likely) the spray pattern is distorted by partial clogging. ( resulting in poor atomization which leads to incomplete combustion ).
Anybody care to weight in on this?
Larry in CA