New to Me EUROBENZO 1986 300d - Page 4 - PeachParts Mercedes-Benz Forum

rjz5400 · #46 06-22-2015, 08:57 PM

SO bad news and good news, Cooling system needs more work, and I added a second set of running lights. I did a write up on them, mentioned that earlier. It is here

I ran down the battery by forgetting I had the lights on, testing the new lights!! So I jumped it and let it idle for a while as I worked inside the house. Maybe 30 min later I went to check on it and found the needle at the very top of the temperature range!!! So I shut it down and popped the hood.

I found the fan was easy to turn by hand, I don't think it does anything as far as pulling in air, and at idle it just had no airflow and got hotter and hotter. The worst bit is.was that the added pressure of the higher temp has pushed out either the gasket or the seal on the water pump and all my nice clean G05 and distilled water leaked right on the ground....... I sure hope I don't have to citrus flush again....... anyway so now it is stuck at my house where I cant really work on it. Ill have to fill it with water, drive it to my land, and pull both the pump and the fan to find out where the leak is, and what is wrong with my fan clutch. I am inclined to add in a relay and a Ford whatever fan with a thermo switch, it sure couldn't hurt the power of the NA, and I also am going to add two bypass holes to the thermostat. it is a genuine Behr/Mahle proper unit. if i have a thermometer I may test it before adding holes.

1. Do you think I will need to reflush for rust/corrosion after having the system sit dry for a few weeks?
2. would the fan clutch alone cause it to overheat like that (ambient temp 95*)
3. Does a bad water pump cause addition pressure to form in the system by not circulating or blocking flow?
4. has anyone replaced seals on a water pump themselves? there are only a couple of parts on it, it seems like a waste to by a new one if it is just a 2.50 rubber seal...

rjz5400 · #47 06-29-2015, 09:36 PM

Well Doesn't seem like anyone cares, just me commenting on here. Oh well good record for if I decide to sell it eventually.

I wrote a taillight how to that went well. I limped it out to the property where I can work on it and I had to jump it on the way. Tested the alternator and found out it was good. I must have a ground problem or something keeping it from charging. Ill check the bulb and the ground strap later.

I also pulled the AL129X from a Saab to upgrade the EuroBenzo, had it tested as well and found it works fine. I ordered a new Water pump (along with primer pump, bulbs, and other randos) and and have decided to add the drain holes to the thermostat as well, while the coolant is out might as well go full on. I am also going to attempt to refill my Viscous clutch as I think thats what started this whole problem in the first place!!

Lastly I figured out why my one headlight doesn't vacuum adjust, it is a Bosch without vacuum adjust! So one HELLA and one Bosch. Both have some broken adjusters and have steam in them (condensation) from intrusion. I am debating refreshing the seals and am also thinking about tinting the frames inside the glass to give it a meaner Euro look.

I thought about doing a how to on the disassembly and Headlight repairs but not sure yet.

Anyway Pics??

Before tail upgrade

After adding a second rear running light

lights let in moisture, see here

disqo · #48 06-29-2015, 10:11 PM

I have been following along. I am glad you are giving this car new life!

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courtney · #49 06-30-2015, 02:33 AM

I am also following your thread!

Great work on the car
i like the 2 tail lights, looks better

rjz5400 · #50 06-30-2015, 07:46 AM

Alright then, I'll carry on. I need to buy a new 10mm wrench to get the water pump off, and some other supplies for my headlight project.

I will get back to the posting in a week or so, once i have something to take pics of.

rjz5400 · #51 07-07-2015, 10:17 PM

Well no pics, hotter than hades out there and didn't stop to take them.

Did get the water pump off although I had to take of the entire pump housing!! They were stuck together and my fan bolts wouldn't come out either. so I released the hoses and took out all those bolts too. Anyway the whole thing is here at home. I had to use vise grips on the fan bolts and a chisel on the water-pump to wedge it off.

Next steps are to clean the pulley and make new gasket for the block water outlet. Then I'll refill the fan clutch, and put that bit all back together. ill maybe wait on the thermostat holes and see if the rebuilt fan and new water pump do the trick.

Ok then....

rjz5400 · #52 08-30-2015, 07:54 PM

Well big update time, I did quite a bit of work. Ill let the pics do the talking but basically.

I cleaned up the alternator, greased the bearing in the back, sanded up all the contact surfaces and cleaned them, after which i put a nice coat of dielectric grease on EVERY surface where power moves. That includes the brackets, bolts, washers, ground strap, cables, washers, and a new positive battery clamp ect ect, ////////

Then I replaced the brushes on my factory VR. I used an aftermarket first, voltage spiked really high!! I hate throwing away a perfectly good part for a wear item like brushes. So I used the soldering iron and swapped the good brushes into the good Bosch VR.

Charging now at a solid 13.5 at idle. Quiet too!!

I also Took apart my headlights to !gently!! clean the reflectors, fix a rattle, and rejuvenate the rubber seals. I had some steam visible in them before. I also wanted to investigate the vacuum on the passenger side not working. Turns out I have one Bosch and one HELLA. so only one has the adjustor.....

Before

Rejuvenating

I began diagnosing the door locks but the replacement Master vacuum switch I had needs a holder and a longer arm, also at least one actuator leaks on both the lock and unlock side so.....
Reservoir tested good, and one way valve did also.

any help I ding the transmission off of this one number? 4 speed manual....

I adjusted the valves to NA specs and noticable improvement in how fast she starts, smoother idle, and possible a little faster but maybe imagination. I also replaced the throttle bushing on the firewall and adjusted the linkage so it now hits the throttle stop at full pedal travel. No pics of the boring bits, just the pointer

Lastly I replaced the three clearish bushings on the shifter side of the manual transmission, no pics, and I have the bigger black rubber ones for the transmission side I just didn't get to it yet.

The only things that are really persistent trouble are the battery which seems to be discharging over time, I suspect it is bad but they refused to replace it so far.... I guess it could be a ghost power draw, ill look extra hard next time I go out the MBZ.

Last thing is them TEMP!!! I flushed filled and replaced the water pump, I also refilled the VC fan clutch and it seems to be working perfectly, it certainly moves a lot of air at idle. the car operates totally normally it idle, heat works, good pressure in hoses, warms up and then stays just below 80c all the time. This is all Without the thermostat. When i put the thermostat back in it slowly overheats at idle, like 90- 100- 110c+ and then i either turn the heat on or shut it down. when driving it is slightly high like between 90-100 but as soon as I stop it creeps up pretty quickly.

Very Frustrating, Mostly because it seems totally fine without the thermostat. BTW the TR is the recommended brand, and I tested it, on the stove in hot water with a thermometer floating in the water. It cracked open at 80-84C was fully open by 90C.

Any Ideas about the cooling system ??
1. recent citric acid flush
2. new water pump (Graf)
3. no leaks, proper level
4. no bubbles or combustion visible
5. metal Fan OG clutch filled with 7500 CST Silicone

MyOld240D · #53 08-30-2015, 09:19 PM

I assume you've already checked these items, but if not, I might help to jog you a little bit. If you're running with A/C on - have you checked the AUX Fan to see if it's spinning properly?

How about the condenser, on the front of the radiator? Might use a good spray out / degrease with the 45* tip on the pressure washer.

You might also think about removing that A/C condenser and giving the radiator aluminum fins a good spray as well.

Just a thought. Nice car and it's nice to see someone revitalizing an old beaten car! Best of luck in your restoration

rjz5400 · #54 08-30-2015, 09:51 PM

Thanks! I haven't removed the condenser/radiator, but i have sprayed them well with the pressure washer. Thanks for the idea though, I suppose it wouldn't be too tough to remove the radiator if I drain the coolant again and clean out between them and better clean the radiator. Ill try it.

The Aux fan is connected but the AC doesn't come on for some reason, so it doesn't either.
It is an aftermarket unit so troubleshooting will probably be slow (the AC)

The car is more neglected than beaten. but it certainly has been on the extended neglect program....

disqo · #55 08-30-2015, 10:14 PM

Enjoying the updates. I have had similar heat problems with air stuck in the system. It seems to help to fill it from the top radiator hose with the car running and on a steep incline.

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MyOld240D · #56 08-31-2015, 12:33 AM

Quote:

Originally Posted by disqo

Enjoying the updates. I have had similar heat problems with air stuck in the system. It seems to help to fill it from the top radiator hose with the car running and on a steep incline.

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My trick for this is to get the car up on ramps with the radiator cap off and rev the crap out of it. Though I did manage once to accidentally diagnose a leaky headgasket when I got a massive coolant geyser instead of the typical bubbling as the air makes its way up...

rjz5400 · #57 08-31-2015, 08:29 AM

Thanks disco yea I remember a guy saying that it turned out to be an air bubble after all that time chasing a cooling problem. I did leave it nose high overnight and will top it off soon to be sure.

I am doing all this testing with straight water also just to facilitate easier swaps....

I think I'll pull the Rad, power wash the whole deal to start clean and fresh, then fill it into every hose separately to try and flush out the bubbles. I haven't really ever had problems like this before with many other 123 or 126 cars.

rjz5400 · #58 09-01-2015, 08:14 PM

So I pulled the Radiator today and did power wash it pretty dang well. I also used some diluted dawn soap to try to loosen any dust, I considered using LA Awesome but didn't in the end. Any ideas on better cleaners? It did make a noticeable improvement but I just feel like it is still pretty dusty like.

Anyway.

I also filled it from the drivers side heater outlet, seemed like maybe the highest input on the block side. I left the upper hose and the block drain open until they had water coming out, then i moved on to the next highest, and so on. anyway seemed like it took a lot of water!! Then I did run it inclined for a while with no cap and then drove it.

It really seemed to do much better. see the pic as about the highest it got! when I was running the AC and a high idle to test the charging system the temp did creep up to 100 BUT the Aux fan doesn't come on with the AC so I attribute the rising temp to that. Otherwise it was completely normal. driving and idling at just above 80 to almost 95 I would guess. This is in ambient temp of 85-90 I think.

Thanks for the Ideas guys!

Also I replaced the primer pump (leaking) and my alternator hybrid VR seems to be working perfectly. See the highest charge number at idle. and the lowest is with the High beams, Fog, Hazard, AC, Fan on high, rear window defroster, dome light, and the Stereo all that load at idle and 12. anything Is good to me. !!

Before, no after WHOOPS!!

Highest "Normal Temp. No AC influence extending idle.

Normal Idle Charging Voltage with No load

MAX LOAD !!!!!

rjz5400 · #59 09-10-2015, 10:28 AM

Well I was using the "backup battery" I got with the car for my tests. It was bad. the AGM That was in it when I bought it also seemed to discharge itself over time so I got that replaced under warranty!!
180$ premium AGM 1000CCA battery is now installed and that 617 starts in a half turn, it did before but now I hope it is going to do that every time!! I am hoping that the discharge I was noticing is just the old batteries being bad and not a light or something on the car. I checked every light and the glow plug relay and found nothing staying on (glow plugs and circuits all tested good )

So status report in case I missed something,
Rebuilt alt charging beautifully
A/C charged and blowing cool (may need to be flushed and refilled I guess)
Adjusted valves, Starts so quickly I need to drive it some
Cooling system is a GO!!! thermostat working normally at proper temp
Headlights reinstalled and looking very similar, have remained clear through rain

Next step is to flush the cooling again and replace the water with distilled and the Zerex z05 I have waiting and drive it on home.

Still left to do.
Motor mounts
some various other rubber bushings and mounts as PM
Clean up and fix the small oil weeps (oil filter housing mostly)
replace oil cooler lines (Eventually, not bad)
track down vacuum lock leak and repair
the seat springs could use some attention but I don't have a good indoor place to do it ATM.

Maxbumpo · #60 09-10-2015, 02:32 PM

I was fearing the worst after your 30-minute idle / overheat / coolant dump, looks like you made it past that OK.