defered maintenance = strange failure

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Larry Velk
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defered maintenance = strange failure

Post by Larry Velk »

Went to the driving range (VERY poor results). Left, car stops 100 m down the road. Tow home. No spark. The car was hot when failed, so did the usual Merkur diagnostics. No LED flash from module connector per Ford quickie test using made up tool (Radio Shack). Got a distributor - why not, as pole piece seemed indicated. I didn't do elaborate tests as we've had these cars for over 24 years and "been there and done that".
Well, this is an '89 and the coolant recovery bottle has leaked for many years at the small nipple - small leak, they aren't easy to find new, and it only needed a cup every so often.
Decided to check the coil as this is easy with a good ohm meter. Out of spec. Removed and took off the rubber baby bumper around the laminations. Rusted! Rust spread out the laminations and shorted the coil.
A Ford coil is very reliable and, IF they ever fail is is often gradual with missing and such. This one failed dead quick. Moral - fix stuff or very odd things can happen.
BTW, on '89's the coil is right under the bottle, so those of you with those old, worn out XR's don't need to worry - just let them leak, I guess.
'86 928, black, 5sp, red full leather, 55k
(daily driver!)
'91 FZR 1000
'64 XKE FHC, in a thousand pieces
2003 BMW Ci (just like an XR!)
'89 XR, red family car
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John Brennan
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Location: Scottsdale, AZ "Summer Is Coming"

Re: defered maintenance = strange failure

Post by John Brennan »

A good cautionary tale... and advice I'm smart enough to understand, and dumb enough to sometimes not take!

This was always my favorite driving range:

Image

It's a shifter kart track built on some property once owned by a friend of mine... but you could (and we did) take cars on it. It's all second gear except for third on the straight, and first at the hairpin... was a great place to try mods, hone skills, teach kids, and just have fun! Too bad he no longer owns it... the building on the left is a half-completed residence/office/hangar (in the middle)... two stories, had a bowling lane underground, and the helipad of course on the north end.

Good times... :(
This is my car, and these are my people!
1989 XR4Ti 5-Speed
2001 BMW Z3 3.0 5-Speed
2015 Fiesta ST 6-Speed
2015 Edge 3.5 V6 Auto/Paddles
itking
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Location: Menomonee Falls, WI

Re: defered maintenance = strange failure

Post by itking »

Larry, you get it running again? My son's XR had the same coil failure. Rust gets in, spreads the fines, & shorts out. We had a spare one. Think its an acer.
Ron
1989 Merkur XR4Ti - Magenta [My XR]
1988 Merkur XR4Ti - Bunny [Wife's XR]
1988 Merkur XR4Ti - Raven [Daughter's XR]
1985 Merkur XR4Ti - Wombat [Youngest Son's XR]
1997 Dodge Ram 1500 4x4 5.9L - Betsy
2002 Buick Century Custom - Daily Driver
1968 Dodge Charger 383
Larry Velk
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Re: defered maintenance = strange failure

Post by Larry Velk »

Yep. Fired right up after the coil - but needed retiming from the dizzy r&r.
Ohms were "only" one third of minimum spec, but factory shop manual says "replace if at all out of spec.". Due to possible corrosion of the blade connector and such, it's a good idea to clean the connector as the resistance specification is quite high, in a relative sense, so even minor corrosion might cause a higher reading putting a bad coil seemingly in spec.
'86 928, black, 5sp, red full leather, 55k
(daily driver!)
'91 FZR 1000
'64 XKE FHC, in a thousand pieces
2003 BMW Ci (just like an XR!)
'89 XR, red family car
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