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texcl 10-16-2013 05:31 PM

going to look at a 300d what to look for
Well, I found a 79 300d near me, it has 140k on it no rust the interior looks great but the passenger side window won't roll up or down and it is difficult to start as per current owner, he says he put new GP's in it. My diesel compression tester broke the other day so a compression test is out, what else should I look for? he says he will take $2200 which I think is a bit high but bet I can talk him down.

Phil_F_NM 10-16-2013 05:59 PM

Lift up the floor mats to check for rust. Check closely on the base of the crossmember below the rear seat for rust.
Check behind the wheelwells and at the jack points.
Take out the first aid kit and reach under the rear window to check for rust.
Lift up the mat in the trunk and look below the spare tire also for rust.

If the window doesn't work, it could just be a dirty switch or a host of other issues all the way up to a bad motor or regulator. Either way, it needs to be fixed and will be a few hours of work at the least.

If the car has a sunroof, make sure it works and then make sure the drain holes aren't filled with pine needles which would lead to more rust.

Check for a squirrel nest. My 300D was formerly a NC car and had at least one squirrel living under the rear seat (lift it up to check) and had a good store of acorns in the ventilation system.

Feel around under the front seats to check for broken springs. Maybe take the seat back off to help with that.

Make sure that all the electrical systems work. Also makse sure the gauges work properly. Check the rear window defogger to ensure it works. Look closely at those elements to see if any are broken or have been "cleaned" off.

Get under the car and try to pull the prop shaft side to side and up and down to check for a bad bearing and or worn bearing carrier. Check the prop shaft rag joints for strings and cracks.

Check the front of the differential for leaks as well as the rear (seal and plugs.) Check the tailshaft seal of the tranny for leaks. Check the oil pan and under the harmonic balancer for oil leaks. Also check the oil cooler hoses and the cooler itself for leaks (do this after the car has fully warmed up.)

Check the AC pump for operation. Check the evil servo base for leaks.

Check under the battery for rust.

Sheck the suspension bushings for cracks. Check the steering box mount for stress cracks in the paint, metal deformation or loose bolts.

Try rocking the wheels side to side to check for worn/loose bearings.

Warm up the transmission and check the lines to the cooler for leaks. Pull the dipstick and smell it to check for burned fluid.

Drive with the window down and listen for grinding in the wheels and squealing in the brakes.

When the engine is warmed up, pop the oil filler cap and see if there is a hurricane of blowby. This may be just a valve adjustment to fix but in old cars it can be worn rings as well.

If you can, pull the valve cover to look for peanut butter covering the camshaft/valve assembly. If you can do this, bring a 27mm socket, a short extension and a ratchet to check timing chain stretch against the mark on the balancer behind the crankshaft pulley.

Bring a vacuum gauge or a mityvac and tie in to the vacuum system somewhere close to the pump line (the first T or Y after the line comes off the brake booster hose.) A good vacuum pump should hold about 18 inches or greater.

If everything works with exception to what you have said isn't working, $2200 is still a high price.

Phil Forrest

junqueyardjim 10-16-2013 06:02 PM

I think you were on the right track when you mentioned compression test. That car isn't going to go fast at that money. Test the compression and you probably won't be looking at replacing the engine. HF compression tester is $30.00 or less and it works great.

cooljjay 10-16-2013 06:15 PM

Lots of money for a non turbo with the evil climate control system....that won't start and has issues...

First assume the milage isn't correct....

Second don't spend that kinda of cash....

Any links to photos or an ad?

Also since this is a 79.....I think it has the strange glow plug relay that is in legs.....replacement price for one is like over 500$.....

rscurtis 10-16-2013 06:30 PM

I agree. I paid $300 more than that for my signature car, and while it was suffering from deferred maintenance, it started and moved (101K miles), and had a fresh brake job including calipers and hoses that I found out after I bought it- and that was over eight years ago.

kerry 10-16-2013 06:40 PM

It's easy for someone to screw up the installation of loop plugs which are OE on that year. If it is the relay, don't be scared off by that $500 since a Ford starter relay will suffice and it's only $40.
Contrary to everyone else, if it has no rust, interior appearance confirms the mileage and the no-start condition is just a glow plug problem, I think it's worth close to that asking price.

cooljjay 10-16-2013 08:57 PM

^^^^ it depends on what year it is and if it will have loop plugs, 1979 was the change over year.....the ones produced toward the end, were fitted with pencil and the really expensive relay. It maybe like mine, which is registered as a 1979 but was produced sept it has the loop.....regardless of the start issue, you still must focus on the evil servo system.....which can cost over 700$ to get working and that's not including the ac side....

Smoker 10-16-2013 09:48 PM

Just drive to NC, there will be a 300CD Turbo up soon that has more new parts than in it than you could haul home in a pickup.....and kills the local mosquito population!

cooljjay 10-16-2013 09:52 PM


Originally Posted by Smoker (Post 3224337)
Just drive to NC, there will be a 300CD Turbo up soon that has more new parts than in it than you could haul home in a pickup.....and kills the local mosquito population!

Well by god, you have the right screen name :P

And who can argue that selling point! :D

unkl300d 10-16-2013 10:17 PM

txcl, my 79 has done me justice, but I have had it garaged always.

I'd check the axle shaft covers for cracks/leaks.

It may not start because it does not have correct valve clearance adjustment.

The loop type glow plugs' relay costs about $250 new.

might be time for new injectors anyway... mine needed replacement around that milage (135K to 150K).

plugged up fuel filters? algae in tank?

Hope the ignition tumbler and associated steering lock is smooth.

make sure trans is OK. (mine OE went out at around 125K miles)

other than that, the klima thing ought to be bypassed. Don't waste money on it, although that might disable your A/C.

The window sounds like a dirty window switch or loose glass from metal frame.(glue it back on or replace window).

right on about checking for mice if the car has been parked outdoor forever !

Smoker 10-16-2013 10:20 PM

That's for sure. Smoker came from my two stroke bikes but fits this car. Just zips down the highway with the needle on the speedo buried. Ton of power. Blowby teakettle test gives a little cap dance but no jumping.

I'm likely changing jobs soon and will be working out of town during the week so it's turned into a bit of a frenzy to finish making the 240 roadworthy

Junkman 10-17-2013 10:42 AM

You have to add a realistic estimate of what repair costs add to the price and go from there. Most can be fixed if you don't mind spending the time.

I'm finding that time is short and projects are many. That's a problem because the mechanics that are able to repair as I want are expensive and I'm cheap.

texcl 10-17-2013 11:12 PM

The car has been kept inside it's whole life, I think I'll wait on a 240d. there is a really nice one in Minneapolis but I've been having a real problem communicating with the person and those deals never seem to go right when they start off bad. I'm sure a good one will pop up. I love working on old diesels and have owned quite a few just no mercedes, we don't really use A/C here just heat. Do these climate control issues affect both or just the a/c?

cooljjay 10-17-2013 11:23 PM

Climate control issues effect both heat and ac on that model....

Do you have an ad for this one? You can share with others?

Why set on a 240D? They are horrifically slow and mpg isn't much greater then a non turbo 300D

Shortsguy1 10-18-2013 12:09 AM

Perhaps he means a w115 240d.

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