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I recently developed a coolant leak on my Kleemann SC system and after checking with the Godfather of all things Kleemann, Cory; he advised that the screws holding the front of the impeller housing on the Johnson Water Pump will get a little loose over time and the pump can start weeping a little bit- not a huge leak, but certainly noticeable.
This past weekend I was able to confirm that the Water Pump was the root cause of the leak and following Cory's advise, I was able to repair it successfully. There was one hitch though, the screws are being held in a plastic housing and I found that one of the screws has stripped the plastic housing, thus there was no tension on that side. For that screw, I had to buy a new screw and nut (pictured below). In any event, I have documented the fix below for my Kleemann SC brothers! First the disclaimer:
IMPORTANT DISCLAIMER: This DYI is to be viewed as a literary work, which is to be used for entertainment purposes only. These are not assorted sets of instructions to assist anyone in modifying, repairing or maintaining a car, motorcycle, truck or any related parts. Working on modern cars and/or car parts is acutely technical, and I highly recommend that you hire a professional to service your car. This DIY contains information about what a professional MIGHT do when working on a car, and equally as important, why they may do it. The author of this DIY assumes no responsibility for inconveniences or damages resulting from use of the information supplied. The consumer or reader is individually responsible for his or her use of the information supplied and uses this information at their own risk. The author of this DIY has no liability for errors, omissions, or any defects whatsoever in the information or instructions, or for any damage or injury resulting from the utilization of said information or instructions.
1. The top view of the water pump housing, the screws circled must be tightened. In the end I found that all 5 screws were loose.
2. The side view of the water pump housing, again tighten all the screws. The screw circled in red was where the coolant was leaking from and was the screw that was stripped.
After 2 weeks, my Water Pump started leaking again. I decided to replace the Johnson C090 with a Johnson CM90 unit. Compared to the C090, the CM90 is heavier duty and can run dry for up to 30 minutes. I posted some pics below.
In my opinion, I may have damaged the old C090 by possibly running it dry when I replaced the Heat Exchanger (when I first replenished the coolant lines). I will never know what the root cause of the failure was, but the leaking started after I replaced the Heat Exchanger. The C090 data sheet says NO DRY RUNNING and even has a big red sticker that says this. I know for a fact I didn't run the CM90 dry for 30 minutes so I should be good now.
UPDATE: Today I re-verified that the coolant leak is gone and so far the Supercharger is feeling great! The Butt-Dyno says that the car feels a little more peppy (with my now upgraded H/E and Water Pump), so I'll be going to the local dyno and confirm my suspicions. If I gained any HP, it was probably due to the old Water Pump going out.
Originally Posted by betrezra
Holy cow! that new pump is HUGE compared to the orig! WOW.
My aftermarket HE is making a HUGE diff in 100 deg F no loss of power like before.
Keeping this thread in my notes for "when" my pump takes a dump.
Kleemann brother #13002
You guys know how hard it is to find any Kleemann SC Specific information on the web, so I make sure I let the brotherhood know everytime I do an upgrade. The new pump weighs more and is larger; so I had to create new brackets in order to get the pump to fit; other than that it's a direct swap.
I've been following your threads too, Jeff! I'm a BIG fan of your paint scheme/mods!
Right now I'm currently looking into CF interior, Coil-Over Suspension, and Eaton SC Porting.
2m--- back at ya! Great combo you got there. Agreed on helping each other out as much as possible. That is a big part of the appeal for me..... You just don't very many modified clk's. it's nice to have something different than a 3 series.
I wanted to update those who upgraded their Kleemannn SC Cooling. A few weeks ago, I was 400 miles away from home and I stopped for a bite to eat. When I returned to my car I found coolant pouring from the car. I was close to a garage (non-Mercedes) and the shop just replaced the coolant hose so I can drive home (side note, my CM90 can run dry for 30 minutes, if this was the original cm090 I would have to buy a new pump).
When I came home I investigated and found the problem was the coupler between the pump and the coolant hose. I decided to upgrade both couplers and the hose clamps and I would like to report that I have no problems thus far. My hypothesis is that the CM90 produces more pressure and thus the hardware needs to be more heavy duty.
The HPS coupler (bought from Amazon) I went with is one size smaller (35mm) than the original coupler, so you have to massage the hose together; but that sucker is not coming off! I have attached a pic to this post.
I have another update for my Kleemann Brothers, I upgraded the hose clamps on my Kleemann Supercharger cooling setup! Before, I used a worm style hose clamp, but now, I use a t-Bolt style hose clamp (more even distribution of clamping pressure). If you are going to do some maintenance on your Supercharger, you might as well upgrade the hose clamps. I bought my clamps on Amazon, HPS model number SSTC-44-51.
UPDATE:I switched from a CM90 to a Meziere WP136S water pump for my Kleemann Supercharged CLK. The CM90 started weeping like the other Johnson pump, so I wanted to try a different style pump.
I bought two of the Meziere fitting 1" barb to -12an o-ring (Kleemann System uses 1" coolant hoses), the supplied O-Ring is good enough to stop leaks.
First impression is that the Meziere is a smaller pump than the CM90 and it must be mounted vertically, so you have to make some new brackets. I didn't find any problems finding a place to mount it.
The car is still running great, she still pulls very hard through the gears! I'm very happy with my setup!
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