I got a set of hella H4 conversion headlamps, and I tried them to see how it fits.  The H4 bulb goes in fine, then you put the rubber cover on, and when you try to put the lamp into the bucket, the rubber cover hits, so it doesn't fit.  It will fit though, with the rubber cover off.

 

Can you do anything besides leave the rubber cover off?  I thought of putting a ring of dielectric grease around the bulb flange, so when you clamp it in, it should seal water out.

 

Is there any other tips?

I know this might not work for you, but since I don't drive my car in the wet, I'd leave the boots off and take my chances.

 

Are the bulb housings you purchased different than the ones they sell in the H4 packages for our cars? I haven't looked into it, but I'd be surprised if the upgrade packages have problems like this. Do they use shallower housings or something?

 

I'm sure you won't like this idea, but you could always cut the back of the bucket out like I did:

 

 

 

I think there is enough depth, but the neck, where the connector is, is just to small for the rubber seal to fit.

 

 

 

I think the dielectric grease will seal it enough for some occasional splashing.  I'm not intending to go underwater!  Haha 

Edited July 30, 20159 yr by TomoHawk

That's strange. I've installed Cibie headlamps on both my 71 240Z and now in my current 76 280Z No issue with H/Lamp boot at all. Perhaps the Hella boot is bigger than the Cibie boot?

 

Picture of Cibie boot.

 

After looking at pictures of Hella boots and Cibie boots, the Hella does appear to be more " bulky ".

I"ll look aroundtop see if thes is a rubber boot that fits more tightly.  Either that, or a duct tape 'boot.' 

I have the Hella's in both my 71's and had no issue with the rubber boot.  Unfortunately I don't have any photos of the install to provide .

We used duct tape to seal the bulb.

Maybe the two of you used different Hella versions? (Are there different Hella versions?)

 

We used duct tape to seal the bulb.

 

Hmmm... How hot do you think the bulbs get?

hopefully not hot enough to melt the dielectric grease used to make the seal.  Maybe we should've used high-temperature RTV silicone?

I doubt the dielectric grease will melt. I was going to suggest RTV instead of the grease though. I mean, how many times do you think you'll be in there changing bulbs? Hopefully never.

 

I don't think you need a hi-temp RTV grade either. I'm sure it doesn't get hot enough to warrant that. I just worry about the duct tape adhesive though. I've seen it get gummy slidey when used on a hot car surface in the sun. Then after a couple months, it dries out and doesn't stick anymore. Adhesive turns to powder.

 

My first thought would be to use some of the non-permanent peelable RTV that they sell for temporary winterizing of your windows.