check your cooling system hoses

[PaulC]

Even if they're new. I neglected to do so and payed the price this weekend.

I was on my way up to the UP to hang out with my sister and two nieces. I didn't leave until late afternoon and was planning on a night cruise. About 220 miles into the trip my water temp gauge started fluctuating between 1/2 and 3/4. I pulled off the highway and found a gas station and started looking under the hood. I could smell coolant and found that the throttle plate to head hose clamps were loose. There was a 24hr car wash there so I pulled into a stall and removed the upper intake, tightened up the hoses, put the intake back on, jacked up the front left side and bled the system.

Got back on the road and everything was fine for about 45 min and then the gauge started rising again. There was a small bank drive-thru right off the exit so I pulled in. It was about 1:30 am so the place was deserted but the lights were on. Steam was rising from beneath the intake somewhere. I removed both the upper and lower intakes and found one of the heater core hoses was wet so I tightened up all the clamps and put it back together. Figured I had loosened something moving everything around the first time. Started it up to rebleed and realized that the heater core hose had a pin-sized hole I had missed.

All the hoses are 6 months old, but I had not retightened them since installing them. Won't make that mistake again. The hose had just collapsed, it had a 2 inch crease in it next to the hole. So I pulled the manifolds off again, removed the bad hose and bypassed the heater core with the other hose. Started it up and rebled the system. Luckily I was carrying tools and fluids. At that point I decided to turn around and head back to Chicago.

I spent about 4-5 hrs in the dark working on the M42. I'm guessing there was still air in the system after the first incident which contributed to the blown hose. That or it was one heck of a coincidence. Good part is that I can now pull apart and reassemble the intakes, throttle body and FI in about 20 min with my eyes closed. Bad part is I damaged the upper intake gasket and now its idling like crap.

Made it back to Chicago safely, but I'm pretty bummed. Learn from my mistake, CHECK YOUR HOSES!

Any comments, suggestions, criticism and flaming are welcome. Thanks for reading.

[nickmpower]

good job keeping a close eye on the temp

[quinn11m20]

Yeah I feel you brother. I used to stare at my coolant gauge a lot. Before I change the Service Interval board, my gauge would twitch. It made me constantly check my temp. Years ago I replaced the radiator after 225k. Well to make a long story short, the upper coolant hose bust on I-95 down here in Daytona. Pulled off to a gas station, NO COOLANT, what so ever!!! pumped it all out. I broke down. I thought that was it for my baby. I didn't know how far I had gone with no coolant. I truly believe it was my choice of oil that saved my engine. Castrol High Mileage 20W50. (Don't worry I wrote Castrol a letter and got free oil and a $100 gift certificate to a local parts store). Sweet Huh? My point is this, even though I replaced the radiator and hoses, I still check them weekly. Its a good thing you do to. Take care.

[PaulC]

Thanks guys.

One other thing I noticed while digging in there is that a few of the vacuum hoses are already cracking. They're new as well, 6 mos old. I'll be deleting that whole mess next time around.

[tjts1]

You're really lucky you kept an eye on that temp gauge. For me the main benefit of deleting the "mess under the intake" was to reduce the number of possible failure points. Good luck
Justin

[PaulC]

Yeah, thanks Justin, your 'mess' thread has a lot of useful info. My main reason for keeping it stock and replacing all the hoses was because winters get pretty cold here, but the more I learn about this car the more I want to modify it. Driving a clean E30 in the salt doesn't appeal to me either.

[Cobra Jet]

just curious about the hoses you were using, since you're saying that they have failed within 6 mos of installation -

Where they BMW hoses from the Dealer, or did you use or purchase hoses from an online vendor?  If the hoses were not purchased from the BMW Dealer parts counter and you did buy them online, what brand or make of hoses are they?

I can't seem to grasp that brand new BMW hoses would start to fail within 6 mos (and how many driven miles)?

[PaulC]

Yeah, I know. Not all of the vacuum hoses are cracking, but at least 2-3 are. Some of the hoses are not from BMW, some are. I honestly can't remember which ones. So there may be an aftermarket quality control issue there. I haven't taken it apart yet, so if I figure out which ones I'll LYK.

[///m42 sport]

Hey Paul i'm interested also since I replaced all my hoses last month.

[PaulC]

OK heres what I found so far.

Vent hose (#10) 11151717858 is beginning to split at the spaghetti/artery end.
http://www.realoem.com/bmw/showparts.do?model=AJ93&mospid=47318&btnr=11_0264&hg=11&fg=15

Air hose (#11) 13411721971 is also beginning to split.
http://www.realoem.com/bmw/showparts.do?model=AJ93&mospid=47318&btnr=13_0307&hg=13&fg=15

The hose which ruptured was the water hose inlet (#2) 64211386690.
http://www.realoem.com/bmw/showparts.do?model=AJ93&mospid=47318&btnr=64_0133&hg=64&fg=18

[PaulC]

Ok so I finally pulled the e30 out of hibernation today. Turns out that the three hoses I listed above are from CRP Industries. A couple more are CRP and don't show any obvious signs of damage.

To my suprise air hose #15 13411721907 has begun to split as well and it is from BMW.
http://www.realoem.com/bmw/showparts.do?model=AJ93&mospid=47318&btnr=13_0307&hg=13&fg=15

I'm deleting the mess. The engine looks so much better without all that crap on it anyway.

[beemer1]

Do yourself a favor and buy high temp heater hose.  I was able to find it at a boating store (Boaters World).  Pep Boys and all other stores in the area had heater hoses, just not the high temp stuff.  

"Deleting the mess" was a pleasure to do.  Simple, easy, and now more reliable.

Can someone answer me, how the hell would you put all those hoses back on the heater plate while connecting the TB?!  Before I started, I took a look at that and began cutting all those hoses thinking it would just drive me insane to put it all back together!

Steve

[e30guydownunder]

no idea on reassembly...my view is throw the lot in the bin!

i did the throttle delte on my road car and on the race car i even deleted the heaterbox circuit.

one thing i will mention is replace the water connection pipe, the plastic pipe on the engine block. My brother did the delete the mess under the intake mod and now about 6 months after that the plastic pipe broke on his way to work....was only just leaking so he got to work but potentially could have been cracked head material.

On the race car we made a steel water connection pipe (as part of the heater box delete) so that one won't break.

[BazE30]

I'm just wondering, are you cleaning the hoses with anything that might react with the rubber causing it to crack?  

It just seems a coincidental that 2 different supplier hoses are cracking all within the same time frame!

[PaulC]

Thanks for the tip about high temp heater hose, will definitely look into it.

The plastic coolant pipe is new. I installed an aftermarket pipe (URO Parts) initially but it didn't fit right. Bought one from BMW which fits correctly.

Never cleaned the hoses with anything.

One thing I can add about this engine is that the CR #'s are kinda high. I don't know if that contributed to the split air hoses but thought it might be worth mentioning. The head appears to have been milled but that is all I know.