K click relay mod to bypass MFRU

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Dave J
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K click relay mod to bypass MFRU

Hi

Does anyone have a link or doc that provides detail on the relay mod to bypass the MFRU please ?

thanks 

Jonathan Kay
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I suggest starting with Andrew Revill's article in Low Flying:

K-Click (amended following subsequent post)

Jonathan

PS: How far have you got in tracking down the cause of the problem?

PPS: You've posted this three times. You can't delete the others but you can change their Subject and the content so that all the responses come in this thread.

 

Dave J
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sadly link doesn't want to work 

Jonathan Kay
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Sorry, how about this?

Jonathan

revilla
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Since writing that I have to say I've rather changed my opinion. Having seen quite a few of these cases I now think that the theories about high resistance in the "weak" relays in the MFRU are nonsense. The MFRU just contains 4 perfectly good automotive relays in a box. In nine if the vmcases that I've looked at have I actually found a oribkem with the starter relay inside the MFRU.

What makes all if the various "relay mods" work (and they usually do) is the fact that they usually involve a short length of stout new wire from the battery to the relay and from the relay to the solenoid.

The voltage drops responsible for K Click are usually along the wiring loom, through fuse box etc. It's removing these from the circuit and replacing with a good short wire that makes the difference.

I'm out today but drop me a PM if you want me to supply details of how I would bypass things now.

Andrew

SV VVC 170 - 170.4 bhp @ 7100 rpm - 142.4 ft.lb. @ 4900 rpm

Geoff Brown
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The other major cause of the click is the fact that the primaries are so close to the starter that heat degradation of the solenoid &/or starter is to me the primary cause of the  problem. 

Having had this problem occur on two successive K series cars all I did was change out the starter for a more (allegedly) heat tolerant starter from Brise & fit an 18g ali heat shield over the whole unit. No hot wire relay mod or similar carried out.

Second K series car ran for six years & 22,000 miles without a hitch - then sold the car & it kept on going according to the new owner.

Original starters lasted 4 years/18,000 miles & 5 years/20,000 miles respectively.

 

revilla
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Yes heat into the solenoid and an already rather marginal performance from the starter at the best of times are a major factor; everything adds up when you have that and wiring issues to contend with, plus sometimes mechanical friction from a solenoid mechanism that could do with a good clean! One comment I would make though; Geoff yours may have been fine but there have been a lot of cases where the Brise starter has caused ECU reset issues though inrush current transients. You end up with a car that needs throttle to start and for a while after starting before it will idle. It's a problem that has been acknowledged by the manufacturer, but I don't think there's a working solution. I would advise a WOSP or Powerlite as an alternative.

SV VVC 170 - 170.4 bhp @ 7100 rpm - 142.4 ft.lb. @ 4900 rpm

Geoff Brown
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revilla #7 - both my Brise starters were of early vintage the last fitted 2005 so maybe the transient current problem is a new(er) occurrence caused by a change in how the solenoid & starter interact with the rest of the car electrics & more sensitivity of later ECUs ?

Dixa1225
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My old car was a 1999 model year. Had exactly the same problem that Andrew described. I refub the old starter in the end.  

anthonym
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Having been touring an an R500-K and its massive heat generation I have suffered I think all of the K Click problems; there are several and as far as I can recall them in no particular order except the first these are:

The thin wire to the solenoid i degraded by heat that reduces the voltage below 7v (iirc) which is insufficient to drive the solenoid. A give away is the wire being stiff when flexed between thumb and forefinger. (The thin wire to the alternator can do the same depending where routed, black I think.)

Same again with the thick wire. Mine snapped when flexed (off the car).

Starter brushes degraded by heat: mine disintegrated when touched.

that's all I can remember, I did write it up at the time at great length but it's now lost somewhere in the old posts. 

Several hours later I have found my old write up in web form, I don't think it was the final one I thought was definitive, but it offers a journey through the click of death practically in real time at the time I suffered it on tour probably over 1,000 miles from home in 2006, where I was rescued by Andre.

http://The_Now_Ancient_Story.html

and 

http://Pedro.html

or loaded in a different way:

https://www.supersevenheaven.com/K-R500/StarterRefurb/

Probably best viewed with both links open as the first refers to many items in the second.

I like to think pictures speak a thousand words. 

edit: looks like some of the full size images are missing, but I think all the thumbnails are there. I'll look for the missing.

edit2 yes it is early in my own click of death journey. It became clear over time there are many causes and no single solution short of getting a slower car (less heat generated, in some cases like an SV massively less.)

As regards the MFRU I dismantled one and was amazed how hard that was to do, far more robust than normal individual relays and won't fill with water in any circumstances. Having replaced one I was convinced had failed and then given the old one away for the new owner to use it with no problems in his car. 

Anthony 

anthonym
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last time I spoke with Tim Brise, which was ages ago, he was saying he can't fix the problem without being sent devices that exhibit the problem. 

If it ain't broke he can't fix it - so I sympathise.

There was more to the conversation about competitors.. mentioned here in #20 as it happens.

Anthony