So i'm the proud, new owner of a far from perfect 1987 300TD but i think i have either a blown HG or cracked head? it is a #14 head and the ruined old fan clutch probably didn't keep the temps down. odo shows 205k. i notice little bubbles coming from the small hose on the expansion tank if i fill it up high enough to submerge it. also abnormal pressure i think. is this hose supposed to be flowing hot coolant? is the radiator blocked forcing it to go through this or something? it really moves when revved. the engine temp doesn't move off 80c and runs great! i think i noticed a thin layer of soot or something floating in the coolant after it sitting overnight. can i tell if its a crack or blown HG without removing the head? what if i keep driving it until i can fix it? doesn't lose coolant, hoses don't have a ton of pressure but still have pressure. where can i get a later head when i'm ready? about how much will it cost? i was really thinking about doing the job myself. am i crazy? ill post pics of the wagon later! here is clip of the bubbles:

[url]https://www.youtube.com/watch?

__________________
83 300CD- sanden, dual p/f condensers, 160a alternator, ect
91 300TD- 722.6, #22 head, 3.5L IP, w140 manifolds, ect

Mine has been doing this from day 1 more than 2 years and 28k miles ago. The way to tell is drive it, park it over night and next morning squeeze the upper radiator hose and see if its heavily pressurized and open the reservoir cap. Does it hiss when you open it the next day? In order to mitigate the problem and extend the life of the head as much as possible, I put a lower pressure reservoir cap off a 190e (forgot the pressure rating) and a colder thermostat (71c I think) and and switched to electric cooling fans ONLY which are turned ON at 82c. Its never gone to 100c and only very rarely climbs about 90c in extreme load /heat situations.

You can probably keep driving it for a long while if its not consuming coolant or mixing oil/coolant but eventually you will have to do something about it. Start hunting for a #17 and up cyl head and put it on your long term projects lists. I have the #17 head waiting in the garage. One of these days I'm going to get to it. Its running so well on the #14 head right now I really don't want to mess with success. 202k miles and counting.

Oh on the cost of the head... they seem to have gotten more expensive lately after people realized they're in demand. I paid $700 2 years ago for my #17 completely with everything (cam, lifters, injectors, headbolts etc). Its still sitting in the shipping box in my garage. I've seen people asking $1000+ for a bare head lately. Highway robbery.

__________________
CENSORED due to not family friendly words

Hi there -

You have made a great choice in cars. These wagons, though lots of work sometimes, are really, really nice. Mine came with a cracked head gasket. Symptoms were very similar to yours; not over heating, bad fan clutch, hoses behaved normally. The dead give away was lots of oil in the coolant reservoir (you don't really have that symptom - totally).

I drove my Klause for 6-8 months with Zero troubles - until I had all the parts together to replace the head. eBay prices on a #22 head (not necessary that you get a #22, a #17 or higher is fine, I even have read that there is a #16, but I don't know much about those) - range from $900 on up. Though I haven't been looking for almost a year, so I don't know what they are trading for these days. They pop up once in a while here on the PP forum. They weigh 50-60 lbs and are expensive. Insist on seeing a pressure test and inspection receipt from a machine shop if you are getting one thru the mail. If inspecting one in person, the cracks are pretty easy to see - there are photos here on PP. They normally form between the IP nipple and the valves.

I made the mistake of buying the expensive Haznet rail pin extractor tool, which I immediatly broke. That job can be done with a stack of washers and a hardened bolt.

Here are the threads I started that kinda document my story form start to finish. It is not an end-all source, but will show you many of the troubles that can pop up. you don't have to replace all the stuff I did.

Shoot anyone here a note, many of us have done this very job. The car is well worth the effort.

http://www.peachparts.com/shopforum/diesel-discussion/339580-1987-300td-i-just-brought-home-car-ill-burried.html

http://www.peachparts.com/shopforum/diesel-discussion/342111-dang-broke-my-pin-extractor-tool-after-only-2-minutes-use-working-my-300td.html

http://www.peachparts.com/shopforum/diesel-discussion/342366-om603-head-removal-last-step-i-hope.html

http://www.peachparts.com/shopforum/diesel-discussion/342541-om603-way-engine-rotation.html

http://www.peachparts.com/shopforum/diesel-discussion/342736-om603-head-almost-off-except-one-bolt.html

http://www.peachparts.com/shopforum/diesel-discussion/346655-ready-thoroughly-flush-my-om603-post-head-replacement.html

http://www.peachparts.com/shopforum/diesel-discussion/350080-klause-running-i-dont-know-why-but-he-runs-drives.html

__________________
1987 300TD named Klause
1987 300TD named Spouse
1987 300D named Seabiscuit
1980 300TD names Chloie (now sadly gone)

Thank you both very much for the replies! well, i suppose it's time to start keeping an eye out for a good updated head. don't imagine i could put a new gasket on the #14 and be go to go? or is it not even worth it because it will probably fail? i refilled the fan clutch with silicone temporarily until i can get a new one with the 606 fan blade. but until then, it fully engages very early so plenty of radiator air flow now. the roar doesn't bother me. what about the coolant flow through the small hose?

__________________
83 300CD- sanden, dual p/f condensers, 160a alternator, ect
91 300TD- 722.6, #22 head, 3.5L IP, w140 manifolds, ect

You said the small hose? You mean the over flow? If the car runs well and doesnt mix oil or use coolant I am skeptical on your diagnosis.

The #14's had bad head gaskets, I would certainly throw $80 at the problem before I throw $1200.

__________________
http://superturbodiesel.com/images/sig.04.10.jpg
1995 E420 Schwarz
1995 E300 Weiss
#1987 300D Sturmmachine
#1991 300D Nearly Perfect
#1994 E320 Cabriolet
#1995 E320 Touring
#1985 300D Sedan
OBK #42

If you keep the rest of your cooling system in tip top shape, and you don't see oil in your coolant. There's no reason to pull the head. If you suspect there is a gasket leak, pull the head, have it tested and go from there. There are several folks on this forum who have #14 heads and have been running them for years. Where you get into trouble is if the engine overheats. The #14 head cannot handle the great and it cracks. Truth be told, a #22 head can crack too (I ended up with one when I was looking for a new head for my car). There is usually a chain of events that leave a trail pointing to the head failure; Fan clutch fails, radiator is poor condition, wrong coolant, driver doesn't pay attention to the temp gauge, boom - temp rises and then boils over, no more coolant, cracked gasket then cracked head.

Drive it for a whole, keep an EAGLE eye on the temp gauge (80 is nominal). You can get the radiator fluid tested for hydrocarbons. Aldo, I'd highly recommend replacing the FSM and clutch.

__________________
1987 300TD named Klause
1987 300TD named Spouse
1987 300D named Seabiscuit
1980 300TD names Chloie (now sadly gone)

If you keep the rest of your cooling system in tip top shape, and you don't see oil in your coolant. There's no reason to pull the head. If you suspect there is a gasket leak, pull the head, have it tested and go from there. There are several folks on this forum who have #14 heads and have been running them for years. Where you get into trouble is if the engine overheats. The #14 head cannot handle the great and it cracks. Truth be told, a #22 head can crack too (I ended up with one when I was looking for a new head for my car). There is usually a chain of events that leave a trail pointing to the head failure; Fan clutch fails, radiator is poor condition, wrong coolant, driver doesn't pay attention to the temp gauge, boom - temp rises and then boils over, no more coolant, cracked gasket then cracked head.

Drive it for a whole, keep an EAGLE eye on the temp gauge (80 is nominal). You can get the radiator fluid tested for hydrocarbons. Aldo, I'd highly recommend replacing the FSM and clutch.

__________________
1987 300TD named Klause
1987 300TD named Spouse
1987 300D named Seabiscuit
1980 300TD names Chloie (now sadly gone)

yes the over flow hose has coolant flowing through it and a good amount when revved. the hoses get hard and bubbles come out of the over flow hose. i didn't know about the #14's having bad head gaskets as well. i just though the heads would crack no matter what eventually. how can one tell if the head is cracked? do you lose coolant, oil, have whit smoke? my cooling system just builds pressure more than normal and kinda looks like it has a sooty layer if i open the expansion tank cap after it resting. it would be awesome if i could just do the HG and fix this. then just keep the cooling system in tip top shape to prevent the #14 from cracking due to heat. BUT, if i find it's cracked upon removal then the car is dead in my garage until i can pay for a new or good used #17+ head IF i can find one

__________________
83 300CD- sanden, dual p/f condensers, 160a alternator, ect
91 300TD- 722.6, #22 head, 3.5L IP, w140 manifolds, ect

i like the idea of the Tstat and lower pressure cap. i don't want a hose to blow or damage the radiator or heater core from this pressure. i'm sure it gets high enough to release the cap's pressure rating on the highway. i haven't noticed any loss of fluids and it seems to drive and run well so i'm really hoping the head isn't cracked to i can do the HG and fix this problem. then i can keep an eye out for a 17+ head for the day it needs it!

__________________
83 300CD- sanden, dual p/f condensers, 160a alternator, ect
91 300TD- 722.6, #22 head, 3.5L IP, w140 manifolds, ect

thank you for the links! i am really digging the w124 wagon and 603 so far but want to get this sorted out so i can move on to more fun things! like the 94+ face lift because the hood doesn't match from hail damage, w210 glass sunroof, some crazy a/c upgrade, ect

__________________
83 300CD- sanden, dual p/f condensers, 160a alternator, ect
91 300TD- 722.6, #22 head, 3.5L IP, w140 manifolds, ect