Hot start 'no crank' 1.9 dg

[sonnyhowell]

Hey guys

I am posting this as I don't seem to be getting anywhere every time i search. Maybe I'm not using the right terms.

I'm having a hot start issue with my vw t25 1.9 dg. It's a 'no crank' so just turn key 'click, silence' all dash lights working as expected

So here's how it happens. Van starts fine from cold and drives beautifully. Once engine has reached full temperature, if I turned off the engine and try to restart.....starts fine. If I leave it for a couple of mins (just enough time to nip into shop or fill petrol) she won't restart.....'click, silence'

Once this has happened it takes at least a full hour till she will restart.

Please please help

Many thanks guys

[captain Byrne]

I have a similar issue but not quite a severe & only occasionally when the engine is quite hot. It could be several things but first I'd check the spade connection to the solenoid is good. I'd just clean it up anyway as a matter of course. Check the gearbox & the main battery earth straps are in good nick & replace if necessary. If you're happy the wiring is good, then I think you're looking at either the solenoid or the motor itself. Both can be stripped down & repaired but you may be tempted (as I am) to get a new starter.

[sonnyhowell]

Thanks for reply. It has already had the solaniod changed and the starter twice trying to solv this. I have had the spade connector replaced also and it's now nice and tight

[captain Byrne]

I'd be looking at the battery, & the earth straps.

[mbcamper]

When you changed your starter motor, did you replace the starter motor bush which is fitted to the engine block next to the flywheel? If this is worn, I believe it can cause hot starting issues, but I'll let others confirm this.

To extract the old one you'll need an M12 tap, and you should soak the new bush in oil for 24 hours before fitting I seam to remember.

Just a thought but electrical connections are worth ruling out first.

[Mr Bean]

My starter motor has an, in my opinion, a rather over engineered right angled connector crimped onto the power lead.
I suffered that same problem and eventually laid under the van with the multi meter probes one on the stud and one on the cable connector while my mate turned the key. When he did that 12 Volts appeared across the two although the nut was quite tight. I took the lead off and brightened the faces with emery and it worked a treat. Although I can't for the life of me see how an invisible film so thin can A - develop and B - provide such a poor conduction.
CS

[sonnyhowell]

Argh!! Banging my head, just done it again. Stranded at Tesco [PENSIVE FACE]


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[philmcC]

I have had the same problem. Checked everything. Confusing because it only happens sometimes and I thought it was related to the aftermarket immobiliser. However having gone over the battery terminals again the new positive clip-on red plastic gizmo type was not clicking home. Once I had sorted that no more problems.philmcC

[captain Byrne]

I have had the same problem. Checked everything. Confusing because it only happens sometimes and I thought it was related to the aftermarket immobiliser. However having gone over the battery terminals again the new positive clip-on red plastic gizmo type was not clicking home. Once I had sorted that no more problems.philmcC

I agree. If you've ruled out the starter & solenoid then you should be looking at the power supply & wiring. I'd start by cleaning and/or replacing battery connections & earth straps.

[chris7ian]

When it's hot the resistance in the (old) wiring is too great to overcome to get juice from the battery... fit a 'Hot Start Relay' which bypasses the ignition switch as the main source and instead just acts as the trigger. Takes a few quid and a few more minutes!

I too had starters rewired, new solenoids etc but nothing solved the problem until I fit the relay.

[Zcat7]

What Chris7ian said.

This problem is really common on T2s and a hot start relay is the answer. The problem is that the starter current has to flow through wiring that runs all the way from the battery/starter at the rear of the van, to the ignition switch at the front, then all the way back to the rear again. As the bus gets old and the connectors and wiring degrade (and get covered in oil!) the total resistance increases to the point that the voltage drop means you can't turn the engine.
The hot start relay only needs a small current to trip the relay contacts (so cruddy old wiring isn't a problem) then the cranking current is passed locally across short wiring - from battery to starter, all at the rear of the bus.

Buy them here https://www.vwheritage.com/ac9112917-ha ... ay-kit-12v or make up the bits yourself from vehicle wiring products http://www.vehicle-wiring-products.eu (or similar).