6/22 Lime Rock Park SCCA Event - PeachParts Mercedes-Benz Forum

Michael · #1 06-26-2002, 08:12 AM

Although it's been touched on briefly by fellow attendees, I thought I'd share with the Forum my recent day at the track.

The local SCCA chapter hosted a "Performance Driving Clinic", open to any and all comers. I showed with my 500E, along with Dave B. with his '92 500E and Jim Norris in his track beast Scirocco. Both Dave and I were running slicks, and were impressed with the additional grip offered. That is, until bathed in Ethylene Glycol. Allow me to explain.

On my 2nd warm-up lap, instructor aboard, I was putzing around warming the tires and likely running at about 40-50%. Well, going downhill thru the right-hander leading to the main straight, my car decides to go into a wildly lurid slide, with the rear stepping out smartly to the left...some way, somehow I managed to collect it, and both myself and my instructor were thrilled. Until we started rotating the other way and off the track!!

Ultimately, beyond about 2 lbs. of turf rammed into my driver's side tire beads, no damage was done. And the culprit was not a set of cold slicks, but rather a ruptured heater hose that barfed coolant all over my rear tires. In about 1/4 mile I lost about 3 gallons of coolant...more effective than Batman's oil nozzles I assure you. I caused several cars to spin, and caused Norris' heart to skip a beat when his front-driver began to oversteer! Thankfully nobody bent anything, and I got my apologies out of the way quickly.

500E owners BE ADVISED: there is a coolant hose that WILL ruin your day, and quite quickly your engine, if it blows at a bad time. The hose connects between the back of the engine block on the driver's side and presumably the heater core, as the hose passes through the firewall. On the firewall side the hose also has a junction that goes off to feed the washer reservoir heater. REPLACE THIS HOSE! Thanks to Alan Tackman for running me around; we didn't even miss a session!

After that little escapade, the car ran fabulously for the rest of the day, although this particular event will not go down in history as having provided much track time. After a PDA event, I usually have to nurse the car to the pumps; after this event, I still had 3/4 of a tank. Oh well, I did pick up some valuable instruction, so Kudos to the New England SCCA for their assistance

It was good seeing Jimbo and David out there; glad to see Dave and Jim's cars held together better than mine! See y'all at the next event...

el presidente · #2 06-26-2002, 10:38 AM

Michael,

Glad to hear both you and the 500E are intact!

Good advice about the coolant hose as a friend is inspecting a possible 500E purchase in the coming days. I'll pass along the valuable info.

Steve

-fad · #3 06-26-2002, 11:06 AM

Hi Mike- glad to hear everything turned out OK.

Q: was it an easy dyi job to swap out that busted hose? were the front/rear connections all within the motor compartment?

any other advice on the install?

tks-fad

Michael · #4 06-26-2002, 11:23 AM

All of the connections are accessed when you raise the hood (send it all the way vertical).

Unless you have fingers coated in Nomex, I suggest doing this repair other than trackside or stranded at the side of the road with a hot motor

Subman · #5 06-26-2002, 03:04 PM

I have had first hand expierence with this hose. I too have a m119 as you all know.
I was on my way home from a day at the track (go figure, good thing it did not blow on the drag strip or I would have been very embarassed). I was comming home and I hit the gass. Next ting I know my radiator lite came on. I pulled in to a gas station. Opend the hood and there was steam everywhere. I had the car towed to my apartement. The next morning I found the hose and had to go to the dealer and have them order it. It cost me $48 with my 10% discount.
Micheal-
Did you hose happen to split where it makes the cure to go into the block?
I had about a 3 inch gash in mine. If I would have let the motor cool and put some "hose tape" on I could have driven it home but I did not want to stand around for 4 hours.

I would go look at your heater hose right now and see what it looks like.

Subman

placo1 · #6 06-26-2002, 04:44 PM

Michael / Subman,

Michael first of all thank god the car is ok! Had me scared when you mentioned you went off the road, don't want any harm to these babies.

I was wondering if either of you do a huge favor and post a pic of this part in the engine bay (preferably Michael). If it's a DIY then it looks like I might have another weekend project coming up but I'd have to see a picture first.

Do you know if the coolant needs to be drained prior to replacement or can I disconnect without worry?

Thanks in advance for the help and advice.

Subman · #7 06-26-2002, 05:09 PM

This is the hose, and it is not as easy as it may look to install. There is a small 3rd line that connects behind the fire wall. I had a hard time connecting it. I had to pull the AC vents/filters to reach it.

Subman · #8 06-26-2002, 05:10 PM

A close up on the section of hose that broke on me.

placo1 · #9 06-26-2002, 06:14 PM

Subman,

Thank you for posting the pics, I'll take a look at mine to determine condition. By the way, THAT WAS FAST, I really appreciate that

Michael · #10 06-27-2002, 06:35 AM

Subman/All-

Yup, that's where it blew! Grew about an inch long slit that purged my system of water quite effectively

The M119 cooling system is self-purging, so if you lose water just top it off.

As to Do-It-Yourself status, I'd say go for it as long as you have a good assortment of screwdrivers and 1/4" drive sockets, since it's tight in there.

To fix this and get back on the grid, Tackman and I sourced a 90 degree hose elbow, a male-male hose connector and a bunch of clamps. I cut out the bad elbow, clamped in the new one by attaching it to the old hose with the male-male adapter, then re-installed. Small hands would help on this job FWIW; I'm gonna have my 8 year old daughter help with this the next time around!

Jim's500E · #11 06-27-2002, 11:19 AM

Here's a question....when the motor's off...is that hose devoid of coolant?

Michael · #12 06-27-2002, 01:20 PM

I'm willing to bet it's full...I think the only air in the entire system, at any point in time, resides in the expansion tank.

By the time I return from vacation next week, all of the engine compartment coolant hoses should be in from Germany so I'll be doing a full system drain & fill. Any/all within striking distance of CT are invited to attend

#13 07-08-2002, 09:44 PM

Hi All,

I am just catching up on my reading after some time off.

Not sure how I missed this thread, BUT......I have pictures!

With Michael's permission I will post pictures of his car while under the wrench, as well as that wonderful turf in your tires!

Those heading to Watkins Glen on 7/22: Driving in that morning (6:30 am start) or the night before? Let me know as I need to make a reservation if we are to meet on Sunday night.

Dave

PS. Thanks to Jim and Michael for the help installing the E-codes....I love them.

Jim's500E · #14 07-10-2002, 08:24 AM

You are very welcome Dave...thanx for buying me lunch !!

I got pics too...one of you Dave in the Esses...and of Micheal's turf tires....haven't yet figured out how to compress the digi-pic down to 65KB though...its a new camera to me. Soon.

#15 07-13-2002, 12:32 AM

As Promised,

Here are some pics of Michael's 500E!

Enjoy.