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Old 07-29-2010, 02:13 AM
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bluebee bluebee is offline
Seek to understand,^Value
Location: San Jose, California
Join Date: Mar 2008
Posts: 25,236
Mein Auto: 02 BMW 525i M54 auto 130K
Here is what I think is the typical recommended special tools and parts list for a 1:1 cooling system overhaul (please correct any errors or omissions):

- 1 gallon BMW antifreeze (~$20/gallon)
- 1 gallon distilled water
- 1 small can of dialectric grease (for electrical connections) (~$5)
a. BMW recommends phosphate/amine & nitrite/nitrate free & low silicate or silicate free coolant (e.g., BMW, Valvoline Zerex G-05, or Prestone Extended Life 5/150).
b. You can "mod" the fluid (e.g., Evans NPG+); but let's keep this list mostly mainstream.
c. A complete cooling system flush will use up to 1.5 gallons of coolant and 1.5 of distilled water; but most seem to get away with a gallon somehow.

- 32mm long & thin viscous fan wrench (EBAY, Harbor Freight Tools, Northern Tools, Pelican Parts, Technitool)
- Fan hub counterhold tool (EBAY, Samsung Tools, Pelican, Technitool)
- Mallet (sometimes needed on the fan nut, especially if you don't have the counterhold tool)
a. These tools are recommended, but you can use a screwdriver or make your own counterhold tools for $10 as per the CAD diagrams in this thread.
b. The I6 uses a 45mm spacing counterhold tool; old BMW P/N; new BMW P/N (most people buy EBAY or tool supplier, not BMW).
c. The V8 uses a 38mm spacing counterhold tool; old BMW P/N; new BMW P/N (most people buy EBAY or tool supplier, not BMW).
d. Consider the EBAY fan nut counterhold tool that I have which has the I6 spacing on one end and the V8 spacing on the other.
e. The BMW 32mm tool (which nobody seems to get from BMW, P/N 11 5 040) has an attachment for a torque wrench; but few torque the fan nut anyway.
f. Technically a 1 1/4" wrench is the same size as a 32mm wrench so check your toolbox (it has to be at least 16" long and preferably < 8mm thick); mine is 4mm thick.

- 1 fuel-line type solid hose clamp for 1/4" ID hoses, 25mm to 40mm (~$1), (Oetiker, Norma)
- 1 radiator nipple, PN (~$3); if you're not replacing the radiator, this is a recommended spare part as it very often breaks.
a. It's common to break the fan shroud seal that surrounds the expansion tank bleeder screw; keep a spare handy (PN 17 11 1 723 580).
b. It's less common to find the two fan shroud 8mm shell, 1mm rivets missing (~$0.25 each); consider a spare set (PN 17 11 1 712 963).
c. The only hose clamp needed for the entire cooling system overhaul is this expansion tank to radiator nipple hose clamp.

- 1 expansion tank (~60 to $75); (Nissens (if available) or Behr).
- 1 expansion tank cap (~$12) (the cap does NOT come with the new expansion tank).
- 1 expansion tank mounting clip (~$2) (this is the clip which goes around the bleeder screw; it often breaks when removing it so keep a spare handy) (Behr, or MTC).
- 2 fuel-line-style solid hose clamps (one for each end of the thin hose at the top of the expansion tank)
a. Only the top (stick) half of the level sensor comes the expansion tank; the bottom (electromagnetic) half of the level sensor generally doesn't go bad and can be re-used.
b. Optionally, you can pick up the electromagnetic coolant level sensor (which plugs into the bottom of the expansion tank to mate with the mechanical (stick) level indication).
c. The expansion tank comes with a plastic bleeder screw (~$2) prone to breaking in half; consider replacing with (~$4) brass aftermarket screws (same size as upper hose screw).
d. There are three hoses emanating from the expansion tank (one on the top, two on the bottom); most don't replace them unless they're obviously worn.

- 1 radiator, ~$150 (manual trans) to $200 (auto trans) (most prefer Nissens over the OES Behr; personally I don't see any reason to reward Behr for making the lousy OEM radiators by buying from them again if you don't have to)
- 1 upper radiator hose, ~$40, (Elaplast or CRP-Contitech but not Uro).
- 1 lower radiator hose, ~$20, (Elaplast or CRP-Contitech).
- 1 temperature sensor ~$20 to $30, a new sensor comes with a new o-ring. (FAE)
- 1 zip tie, about 8 to 10 inches long (ties a plastic wiring harness to the upper radiator hose)
a. The new radiator comes with the expansion tank top hose nipple so the nipple part number isn't listed in the REALOEM diagrams.
b. If you're working on the fan shroud, it's common to break this nipple; keep a spare handy (PN
c. The upper radiator hose comes with a plastic bleeder screw prone to breaking in half; consider replacing with brass aftermarket screws (same size as expansion tank screw).
d. The lower radiator hose does NOT come with the temperature sensor; so if you re-use your old temp sensor, buy a new 8mmIDx3mm thick O ring (PN 13 62 1 743 299).
e. You can "mod" the radiator by going all metal (e.g., Zionsville); but this post is about the typical recommended replacement parts.
f. The radiator comes with the blue radiator drain plug.

- 1 mechanical (up to and including 1998) (~$100) or electrically heated thermostat (1999-2003) (Wahler) with O-ring gasket (~$2)
- 1 housing for the mechanical thermostat (not needed for the electrically-heated thermostat) with O-ring gasket (~$2)
a. You can "mod" the mechanical thermostat housing by going all aluminum; but make sure your mating surfaces are precisely flat.
b. RTV or thermostat gasket/seal for thermostat housing (e.g., Goetze) is not needed nor recommended.
c. The electrically heated thermostat is integral with the plastic housing so you do not need a separate thermostat housing.
d. Some people mod their thermostat by going with a lower temperature and/or by drilling air-bypass holes in the thermostat.

- 1 water pump (~$125 to $150) with o-ring ($3), (lots of debate ... Hepu & Graf are good, GMB is BMW OEM, GEMP/Stewart is high end)
a. Optionally you can replace the glass-filled plastic water pump pulley ($25); but most replace only if damaged.
b. Having said that, those who use a BFH and just the 32mm wrench often damage the pulley; so either buy the pulley holder or keep a spare pulley handy before you start the job (lesson learned ... see details below).
b. Optionally you can replace the 4 water pump pulley bolts; but most replace only if damaged.
c. Optionally you can replace the 4 water pump pulley nuts; but most replace only if damaged.
d. There is intense argument about water pumps, mostly about plastic versus metal impellers and long life.

- 1 fan clutch ~75 to ~125, (Behr or Fichtel-Sachs, maybe even ACM; but not MTC, Mission Trading Company)
a. The viscous fan clutch and the plastic blades are two different parts; most replace the clutch; some replace the fan blades.
b. Optionally replace the fan blades (~$40 to $60); but most replace only if damaged (Behr OEM, Febi-Bilstein, or Meyle, or ACM)

- There are no recommended parts for the engine block; but see optional parts below:
- Optionally, on older E39s, if you flush, you may require 1 engine block water drain plug (see cn90 cooling system overhaul DIY)
- Optionally, on older E39s, if you flush, you may require 1 engine block water drain plug washer (see cn90 cooling overhaul DIY)

ODDS & ENDS (most of which were covered in specific sections above):
- Extra radiator nipples (BMW PN
- Extra green coolant temperature sensor o-Rings 8mmIDx3mmthick (BMW PN
- Extra fan shroud rivets for 8mm holes (BMW PN
- Extra brass bleeder screws (aftermarket), ~$4
- Extra fan shroud seal surrounding the expansion tank bleeder screw (PN 17 11 1 723 580).
- Extra hose clamp (fuel filter solid-band type, for ID 1/4")
- Extra 10-inch long zip ties (to secure plastic wiring harness to upper radiator hose)

Here is a real-world example parts list from cn90 back in 2006 for a 1998 528i. Notice the choices made, the need for multiple suppliers, and the prices paid ... (YMMV).

1. From the BMW Dealer:
* Thermostat Plastic Housing (PN 11531740478) $28.00

2.From AutoHauzAZ http://[URL=""][/URL]
* Behr Thermostat 88°C (PN 11531721002) $17.00
- Note: The factory thermostat is 92°C, but I wanted it a bit cooler. Now the temperature gauge sits just a bit LEFT of the 12 o’clock position when warmed up.
* Radiator hoses (upper and lower): $9 and $7
* AC belt (5PK0906) $9
* WP-Alt-PS belt (6PK1560) $13
* Rollers x 2 (PN 11281748131) $17/each
- (for the AC belt and for between the crank and WP pulleys)
* Idler Roller (PN 11281738605) $23/each
(this sits between the WP and alternator pulleys)
* Hydraulic Tensioner (PN 11281717210) $39/each
(for the AC belt)
* Hydraulic Tensioner (PN 11281717188) $50/each
(for the roller between the crank and WP pulleys)
* Coolant Reservoir "Mounting Clip" (PN 17111723580) $2.20/each
* Fan Clutch by "Sachs" (PN 11521719269) $94/each
* Fan Blades by "BMW" (PN 11521712058) $45/each
* Radiator by "Nissens" (PN 17111702969) $173/each
(many people consider the Nissens to be better than the Behr radiator)
Bluebee note: Plus why reward Behr by buying ANOTHER of their radiators to replace the broken one!
* Bypass Hose from Radiator to Reservoir (PN 17111427156) $5.60/each
(This is also known as the reservoir overflow hose, which is located along the top of the radiator going from the reservoir nipple to the radiator nipple)

3. From BMW-Parts Direct http://[URL=""][/URL]
* Coolant Vent Screw (PN 17111712788) $2.80/each
* Reservoir Cap (PN 17111712669) $10.60/each
* Reservoir by OEM (PN 17111723520) $56/each
* Water Pump by "Hepu" (PN 11511740241) $67/each
The pump came with the o-ring. Based on research, the "Hepu" waterpump seems to be a bit better than the "Graf" or "Geba" (Graf and Geba seem to have leakage after 20-30K miles but I am not sure). The Volvo folks love the Hepu water pump so I went with "Hepu".

Please correct the errors/omissions in this list so we have a good starting point for the next person who needs a cooling system overhaul parts list.

Last edited by bluebee; 09-26-2010 at 07:34 AM.
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