83 to 85 Differences - Page 2 - PeachParts Mercedes-Benz Forum

dkr · #16 01-24-2018, 07:17 PM

Quote:

No major swap issues, since I installed a ~1982 engine into my 1985 CA 300D. It has the later 722.4xx transmission, which I understand has slightly higher gearing, though that might be the rear-end. I even kept the frame-mounted air cleaner (cut outlet tube shorter to match turbo inlet). On my 1984 300D, I went the other way, installing a 1985 CA air cleaner (no more shaking) and the blue saucer buffer amp for the tranny vacuum signal.

I was thinking of installing a 1985 CA air cleaner for the same reason. Was it a bolt-on or more involved? I wasn't sure if the oil drain or anything else would need to be modified.

Dkr.

R-3350 · #17 01-25-2018, 12:15 AM

the tach amp is located in the EGR computer not the plug under the hood in the 85' models they also have two hall effect sensors one like all the other 617's on the crank and one behind the oil filter housing in the trans adapter plate. the 722.315 behind the 85's has a higher stall torque converter to help acceleration with the 2.88 rear end. the speedo is geared for the 2.88 ratio. the injection pump has the rack position sensor on the inboard side in all 85' and cali 84' cars. the turbo compressor housing is different as well for those same years and requires you have a matching filter housing and u tube to clear the ARV. the EGR system is much more complex and uses multiple solenoid valves and vacuum valves all hooked to the controller module in the passenger foot well. other than that it is all the same as far as i know almost all the hard parts are interchangeable some with a bit of work but still.

michael0584 · #18 01-25-2018, 09:43 AM

Quote:

Originally Posted by R-3350

the tach amp is located in the EGR computer not the plug under the hood in the 85' models they also have two hall effect sensors one like all the other 617's on the crank and one behind the oil filter housing in the trans adapter plate. the 722.315 behind the 85's has a higher stall torque converter to help acceleration with the 2.88 rear end. the speedo is geared for the 2.88 ratio. the injection pump has the rack position sensor on the inboard side in all 85' and cali 84' cars. the turbo compressor housing is different as well for those same years and requires you have a matching filter housing and u tube to clear the ARV. the EGR system is much more complex and uses multiple solenoid valves and vacuum valves all hooked to the controller module in the passenger foot well. other than that it is all the same as far as i know almost all the hard parts are interchangeable some with a bit of work but still.

Thanks, I have my EGR bypassed anyway. Trying to keep the intake a little cleaner and supposedly the turbo and injection pump have already been removed from this car.

BillGrissom · #19 01-25-2018, 04:04 PM

Quote:

Originally Posted by dkr

I was thinking of installing a 1985 CA air cleaner for the same reason. Was it a bolt-on or more involved? I wasn't sure if the oil drain or anything else would need to be modified.
Dkr.

Search for my posts w/ photos. The correct PN air filter element is >$50, so I just stack 2 shorter filters (gave Wix PN many times, for Toyota MR2).

In my 1984, I recall drilling at least one hole to mount the 3-legged bottom support for the 85 CA air cleaner. I think there were already holes for some. I removed the silly aux water pump in both cars, so no issues there (still plenty of heat). The AC suction hose is routed slightly shorter in 85 CA, since I had to bend the 1982 engine's tube to reach my 1985 car's hose. That was likely to clear the air cleaner. But, I recall no problem in my 1984. The hose does route over the air cleaner, but can still easily swap filters. Anyway, I replaced all AC hoses in both cars (just the rubber). The high-pressure AC hose and tubing is slightly different in 85 CA, probably to better clear the air filter housing. I re-routed that in both cars, going straight over to the AC condenser instead of the Rube-Golberg route up L side of the engine which made it hard to get at the alternator bolts. But, I recall after I retro-fit the air filter on 1984, so "should work".

85 CA tee's the valve cover vent oil drain right into the turbo inlet duct, which I thought stupid unless you like oil gunk on your compressor wheel. Since my 1982 replacement engine had an oil drain tube (as did my 1984), I tee'ed a tube over to the factory drain tube. That still sits by the turbo exhaust bellows (where air cleaner oil separator used to drain), so the tube runs across to there w/ a slight gradient. Whatever size tube I used (3/8"?) fits snug in the drain tube and I used an O-ring and rubber umbrella to seal. You could fab a drain tube directly to the oil pan (run behind alternator). Initially, I used the 85 CA tee, but the rubber was old, so changed to a silicone tee made by cutting a coolant hose from a motorcycle kit (cheap on ebay). If I ever go back to the 85 CA engine, it doesn't have the oil drain stub on the upper oil pan (just big stub for turbo oil). As mentioned, I had to cut the air filter outlet tube ~1.5" shorter to match the lower turbo, using a silicone elbow w/ flat duct clamps (after-market, ebay).

There are many oil separators in turbo-tuner world. Some just collect it in a catch-can you regularly dump. One M-B diesel after-market one drains it on the ground (thru hole above suspension spring). Not too evil since asphalt is made of oil and thru the 1970's they regularly sprayed oil to rejuvenate it. It feels like the oil drain stub has a weak check-valve when you blow thru it. Not sure why it would need one since both points connect to the same crankcase pressure, thus gravity should suffice.