Clutch Interlock Switch Bypass

jrcotner

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New Ulm, MN
I want to bypass the clutch interlock switch on my '05 Rubicon and consulted my owners manual for guidance. Page 186 of the manual states that a 20 amp fuse needs to be installed in slot #28 in the the engine bay fuse block. So I got a spare 20 amp fuse, installed it into slot #28, and it won't lock into place. So I decided to try a jumper wire, but when I slid it in it went through the fuse block. Seems there are no contacts in slot #28. To further confuse the issue, page 294 of the manual shows that slot #28, Clutch Override, requires a 10a fuse. The manual doesn't agree with itself. Does anyone else have this fuse set-up in their Rubicon and, if so, how did you bypass the clutch safety switch?
 
On a Rubicon all you have to do is put it in 4L and the clutch switch is bypassed. You are correct in that the
Rubicon fuse slot is not populated.

If you want to permanently disable it, you can jumper the switch on the clutch pedal under the dash.
 
Thanks for the info. I've looked all over the infowebs and there seems to be a lot of variation between years and models. And in my case disagreement between the owners manual and actual vehicle. I tested to make sure it will start without stepping on the clutch in 4 low. I'll look for a wiring diagram to see about bypassing the switch with a jumper wire.

Why do I want to bypass the clutch interlock safety switch? I'm old and it irritates me.
 
The clutch ignition interlock switch is attached to the clutch pedal under the dash.
You can slip a solid core jumper wire between the two wire terminals in the switch connector.
Shouldn't take but a minute or so to accomplish.
 
Thanks for tip. I'll wriggle my sorry self under the dash with a jumper wire and sort it out.
I was lucky, mine failed in the shorted position yrs ago, so it starts just like my YJ now.

Not that you care about it, but there is a recall on the switch.

Also, the fuse overide on the non Rubis will light the 4WD light continuosly, which is annoying.
 
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If you stop on a steep hill offroad, you can start off without using the clutch which prevents rolling back, slipping clutch, etc, etc.
X2. It can also eliminate the chance of muddy water from flowing in between the clutch disk and pressure plate too by not having to push the clutch down to use the starter motor to either start the engine or to use the starter motor alone if the engine won't start to get you out of deep mud/muddy water.
 
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I used to have a 75 dodge power wagon, 5 speed with granny gear,they didn't come with clutch interlock. I could get it to almost jump sticks with clutch out, gas to the floor and start it 1st gear.
 
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Thanks for the info. I've looked all over the infowebs and there seems to be a lot of variation between years and models. And in my case disagreement between the owners manual and actual vehicle. I tested to make sure it will start without stepping on the clutch in 4 low. I'll look for a wiring diagram to see about bypassing the switch with a jumper wire.

Why do I want to bypass the clutch interlock safety switch? I'm old and it irritates me.

You have something else going on if you have a Rubicon, you had it in 4 low and it wouldn't start with the clutch out. There is a fuse slot under the hood that you can use to bypass it. It says something like Offroad on the label for it. It does turn the 4x4 light in the cluster on though which is annoying.
 
Having a bypass is also a little nicer to the crankshaft thrust bearings when starting. Especially after sitting for long periods or extended cranking.
 
Having a bypass is also a little nicer to the crankshaft thrust bearings when starting. Especially after sitting for long periods or extended cranking.

Yeah, you're gonna have to walk me through that one and how the thrust bearings care when they endure other loads that bring them into use with ease.
 
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Thanks for tip. I'll wriggle my sorry self under the dash with a jumper wire and sort it out.

If you ever take your vehicle in for service or anyone else drives it I would suggest adding a switch where you can turn the bypass on and off. I worked in the auto industry for many years and have seen enough vehicle stared in gear driving into benches, other vehicles and even people.
 
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Yeah, you're gonna have to walk me through that one and how the thrust bearings care when they endure other loads that bring them into use with ease.

I think it has less to do with the load and how it is applied vs the lack of oil film present after sitting for extended period of time or cranking dry. There was an article in engine builder magazine years ago that examined the relationship between clutch pressure on the crank during startup and thrust wear.
 
Ive had an 05 TJ and now an 06 Rubicon. In the non rubicon you could relocated the fuse under the hood and it would start without clutch. In the Rubicon the fuse swap does not work but then engine will start without pushing clutch if you have the transfer case in 4LO. I have become very used to starting that way in tough conditions or higher water/mud, I've killed the engine more times than I want to admit. Works very well to start win 4LO in 1st or 2nd gear, no clutch. Anyone that has a manual should try it to gain confidence.
 
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I think it has less to do with the load and how it is applied vs the lack of oil film present after sitting for extended period of time or cranking dry. There was an article in engine builder magazine years ago that examined the relationship between clutch pressure on the crank during startup and thrust wear.

Got it, I had to think about it a fair bit to arrive at a similar answer. Probably me being sensitive about being raked over the coals over a rear main seal leak after a trans swap. The guy took it to his mechanic who told him that we let the trans hang on the input shaft which deflected the crankshaft and ruined the rear main seal.

I explained that it doesn't work that way, at all. First, the alignment dowels/sleeves engage about the same point of depth as when the input shaft engages the pilot bearing so there is not really any way to hang it off of the input. If you could do that, it would bend the input, ruin the pilot bearing and just make a mess.

Then I asked him how much oil pressure he lost. He wanted to know why? Well, in order to deflect the rear of the crank at that main bearing enough to ruin the seal, we would have had to wipe out that bearing and you would notice a serious loss in oil pressure.

Neither him or his mechanic had a good answer for that one.
 
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Thanks for the info. I've looked all over the infowebs and there seems to be a lot of variation between years and models. And in my case disagreement between the owners manual and actual vehicle. I tested to make sure it will start without stepping on the clutch in 4 low. I'll look for a wiring diagram to see about bypassing the switch with a jumper wire.

Why do I want to bypass the clutch interlock safety switch? I'm old and it irritates me.

We didn't have that crap when I was growing up - you knew to either step on the clutch or put the thing in neutral.
 
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