the flyin' scotsman

Alan...........do you know why the bulb connectors would get burned?..........water leakage causing shorts?

ZEUS+

Poor connections with high current draw generates heat.

the flyin' scotsman

.....and in this specific case of the 928 headlights?

ZEUS+

If changing the connectors and bulbs fixed the problem, yes. Was there moisture in the headlamps ?Headlamps draw alot of current.

borland

Relay socket repair kit:

http://cgi.ebay.com/ebaymotors/ws/eB...m=330072142870

the flyin' scotsman

Realise that but was curious as to the design...........would you expect same in a 20 yr old North American car?.............my car has only 150k kms on it and in the last 5 years I put on 50k of those 'miles' and very few were at night............I want to do hi- speed in the daylight.

Just my experience but I found out the hard way; rural road at 6am and pitch black sky.

Alan

Malcolm,
Pretty much what Zeus said... its poor connections that cause heat. Initially water ingress can cause corrosion that causes increased contact resistance - this causes heat and heat makes things worse causing more corrosion & oxidation and so it deteriorates...

The H5 connectors (US DOT) are good for preventing water leakage but have a very small surface area so fail rather quickly (especially with higher wattage bulbs and and any poor connection - say not fully plugged together).

The H4 Euro connectors have far worse moisture protection but have physcally much bigger terminal connections and usually also have a higher mating force, they also can be cleaned quite effectively (both parts) chemically or physically. Overall they seem superior esp for higher wattage bulbs.

Alan

the flyin' scotsman

I see..............what would you recommend to prolong connector life; Dave in CA swears by a subsatnce I can't get locally (at the JD parts counter anyway). Stabilant

My '03 Chev truck has 116k kms on it; dont expect it to have burnt connectors..........technology?

Alan

Malcolm - well you could buy some H4's and everything would be very happy except your wallet!.

Stabilant would be good but in this case with new connectors - you could get some kind of basic switch cleaner to clean the bulb terminals (a bit of gentle rubbing with a cotton bud may help get them squeeky clean - then apply a simple non-conductive paste or spray on dielectric (say battery spray). You are not looking to clean anything at this point just seal the connections from both water & oxygen. You rely on the contact pressure to clean the dielectic material off the mating portions - since it doesn't help the connection at all - just protects them from later degradation.

I think this would work fine for you - make sure the plugs are well mated and secure. keep the bulbs stock for longer life (check what you have in there)

Alan

the flyin' scotsman

Alan..........lots of other winter projects so H4's aint in the budget.

Now that I'm getting to grips with posting pics and such I'll take a few of the old connectors..........judging by the screws et al I was the first in there after Hans and Frans hence my question re. design.

Bill..............at least check out the connctors; 2 screws on the shells

Bill Ball

It was both high and low, but it appears that reseating the relay fixed it. The ride home tonight was fine.

If both high and low spades are on the top of relay, then they could have both lost contact when the relay pivoted out from the top. However, the flickering was IDENTICAL on both sides, and you would not expect two spades to lose contact EXACTLY the same way. And if those spades are not on the top, then that's just not it.

So, I would suspect you must be on the right track with the limit switch. The switch can be opened up and cleaned, right?

You sure are right about H4 connectors. They are totally exposed. I thought I was missing a boot when I converted from H5 to H4, but there is no boot for the H4 plug. The headlamp bucket is not sealed against the lamp housing, so moisture in there is inevitable. However, my connectors still look fine. I have seen lamp housing frames from other cars that must have been in the rust belt, where they use salt on winter ice and snow. The looked awful. I can't imagine the H4 connectors doing very well in that environment. It's strange to me that they are completely exposed.

Anyway, I will have a look at the limit switch even though I had no trouble tonight.

SharkSkin

Bill, any sign of melting on the socket? Might be time for a remote relay with those aircraft landing lights you have on there....

Bill Ball

No, Dave, everything looked fine - like brand new. Despite that fact that I'm running 100/80W, the fuses are still stock 7.5 and the wires do not get warm. Only thing was the relay socket's female connectors were loose on some of the relay spades. I'm going to snug them up, but I'm still puzzled how both hi and lo beams flickered the exactly the same, so I need to at least open up the limit switch.

SharkSkin

Bill, couldn't it just as easily be the connection where the limit switch connects back to the relay?

Bill Ball

Ah! I neglected to trace that back, but, of course. Thanks, Dave.