Engine swap changing coils, What size / type coil? Options

[jsaum]

I'm in the middle of an engine swap and am so close to getting my car on the road I can barely stand it! I'm putting a 1.8 motor from a 75 into my 72 and found that the size of the coil that normally mounts to the engine tin is different from the one that has the bracket that mounts on the blower housing. Does anyone know the correct part number or coil to use for that mounting bracket?

Thanks,

Jsaum

[Cap'n Krusty]

They take the same coil. The most common replacement coil is the Bosch "Blue" coil. Modern replacement coils are smaller in diameter than the original version. A few layers of strips of duct take can be used to correct the difference in size. BE SURE you use a coil with the correct internal resistance. 914's and most other German cars of the era do not use external ballast resistors.

The Cap'n

[jsaum]

Maybe the bracket is bent or would there be a stud in this location and secured with a nut? There is about 1 1/2 of an inch distance from the housing when I have the bracket in place wrapping around the coil.

[Dave_Darling]

Look up on the engine tin. You'll find two holes with weld-nuts. Those hold the original coil bracket onto the tin, at least on earlier cars. (I think some of the 1.8s had the coil where you show it? But I'm not sure.)

The bracket that comes with the Bosch blue coil does not work with those two holes, unless you are willing to use and trust some very large fender washers. The new bracket is shorter than the old and the holes don't line up very well at all.

I used a piece of bicycle inner tube wrapped around the coil to get it to fit the old bracket. It has worked fine for many years. I have heard stories of duct tape adhesive softening over the years and allowing the coil to move around.

--DD

[ThePaintedMan]

I used a piece of bicycle inner tube wrapped around the coil to get it to fit the old bracket. It has worked fine for many years. I have heard stories of duct tape adhesive softening over the years and allowing the coil to move around.

--DD

(IMG:style_emoticons/default/agree.gif) DON'T use duct-tape, unless it's just to get home. The heat from the engine will melt the adhesive quickly. Also, the neoprene I used originally had lost some of it's shape and the coil eventually worked its way loose... and promptly fell into the fan area. Luckily when I got to work I noticed what had happened. Ate about .5 inches out of the coil, but it still functioned.

I've since used a split section of hose to use as a rubber buffer between the bracket and coil... and of course, replaced the coil for good measure. (IMG:style_emoticons/default/headbang.gif)

[Cap'n Krusty]

I used a piece of bicycle inner tube wrapped around the coil to get it to fit the old bracket. It has worked fine for many years. I have heard stories of duct tape adhesive softening over the years and allowing the coil to move around.

--DD

(IMG:style_emoticons/default/agree.gif) DON'T use duct-tape, unless it's just to get home. The heat from the engine will melt the adhesive quickly. Also, the neoprene I used originally had lost some of it's shape and the coil eventually worked its way loose... and promptly fell into the fan area. Luckily when I got to work I noticed what had happened. Ate about .5 inches out of the coil, but it still functioned.

I've since used a split section of hose to use as a rubber buffer between the bracket and coil... and of course, replaced the coil for good measure. (IMG:style_emoticons/default/headbang.gif)

Musta been el cheapo duct tape. I ran my T4 in the bus for 10 years with a duct tape wrapped coil. (Things connected to me have a way of being exceedingly cool, so heat might not have been a factor ...........) I'm not saying it's the best way, but its "a" way. The hose sounds better, but one would have to be VERY careful about the thickness.

The Cap'n

[jsaum]

Look up on the engine tin. You'll find two holes with weld-nuts. Those hold the original coil bracket onto the tin, at least on earlier cars. (I think some of the 1.8s had the coil where you show it? But I'm not sure.)

The bracket that comes with the Bosch blue coil does not work with those two holes, unless you are willing to use and trust some very large fender washers. The new bracket is shorter than the old and the holes don't line up very well at all.

I used a piece of bicycle inner tube wrapped around the coil to get it to fit the old bracket. It has worked fine for many years. I have heard stories of duct tape adhesive softening over the years and allowing the coil to move around.

--DD

I'm using the engine tin from the 1.8 so it doesn't have the holes to mount in the other position. The engine is already in the car or I would just swap them out. I'll figure it out in a few days and post more pictures. My problem is the coil is to big and the clamp won't fully cover it as I would expect. Once I hook the clamp into the blower housing and hinge it over the coil there is a distance one to one and half inches from the bracket to the housing.

[Cap'n Krusty]

Might want to give us a picture of the coil and the bracket ....................

The Cap'n

[worn]

Maybe the bracket is bent or would there be a stud in this location and secured with a nut? There is about 1 1/2 of an inch distance from the housing when I have the bracket in place wrapping around the coil.

My 76 2.0 has those holes and the coil was mounted on the case in the back as in the pic. PITA and hot to get to. The first clue that this wasn't ideal was at an evening autocross events in which the engine was misfiring and blue arcs were all over the engine bay. The coil had fallen out and was dragging by the wires.

The bracket uses a long screw the same pitch as the engine tin. You bend the stock bracket to fit into the top and then use the long screw to pull things tight. Problem is it starts to get tight with a lot of space between the bracket and the housing so you feel like you are squishing the coil (source of my problem was being scared to go tighter).

So I have switched to the engine tin location as suggested. I also have taken to liking the epoxy potted anti vibration coils. I have a "Blaster" (IMG:style_emoticons/default/lol-2.gif) , but there are a lot of them out there. My idea is that the coils fail from wires eventually parting company inside. Don't know if that is true but they aren't pricey.

[sean_v8_914]

i do not recommend "on the tins" mounting location. i have welded up way too many coil mounting areas on teh tins. i like the fan shroud clamp with the bike tube rubber wrap

[Drums66]

i do not recommend "on the tins" mounting location. i have welded up way too many coil mounting areas on teh tins. i like the fan shroud clamp with the bike tube rubber wrap

...I 2nd this! (IMG:style_emoticons/default/thumb3d.gif)
(IMG:style_emoticons/default/bye1.gif)

[worn]

i do not recommend "on the tins" mounting location. i have welded up way too many coil mounting areas on teh tins. i like the fan shroud clamp with the bike tube rubber wrap

So I am assuming that the bike tube is there for extra friction? The stock coil on my '76 with a stock bracket still required a screw at least an inch long to get the bracket started, and when tight still had a lot of gap. That sounds OK, but because the screw never went all the way to the housing it never torqued tight against anything. Vibration would generally loosen it (after I made the mistake of removing it and the rust etc). That was why I eventually moved. Fits perfect. Is it the weight of the coil that the tin cannot abide? The clamp certainly wasn't stretching anything. Would locktight be in order if the coil was moved back again?

[jsaum]

OK I got this picture on Google for a VW type 4 so maybe I have a bracket that went on a type 4 bus engine that uses a smaller coil? I was expecting the bracket to mount flush like this picture.

[jsaum]

OK I got this picture on Google for a VW type 4 so maybe I have a bracket that went on a type 4 bus engine that uses a smaller coil? I was expecting the bracket to mount flush like this picture. Maybe I need to buy the Red Bull brand coil!

[Dave_Darling]

With the extra holes on that, I'm betting that it's a "custom" bracket made out of plumber's strapping.

--DD

[Cap'n Krusty]

With the extra holes on that, I'm betting that it's a "custom" bracket made out of plumber's strapping.

--DD

Nope. That's the factory bracket. Let's see a picture of the cil in question.

The Cap'n

[zambezi]

Yup, stock bracket. You can just barely make out the raised square section of the factory bracket.

[jsaum]

OK I think I figured it out probably the bracket was bent up so I tried to bend it back and then used a longer bolt to secure the coil in place. I still have a little gap between the bracket and the housing. I used a nut and some lock washers to secure it. On to hooking up the rest of the electrical and maybe a running car again!

[Cap'n Krusty]

Way to go. I would put a nut and washer between the bolt and the fan housing. Lock it either against the bracket or against the shroud once you've tightened it all down. Maybe you've done that already, but it's not in the picture.

The Cap'n

[jsaum]

Yes I did put a nut there so it shouldn't back out on me. Thanks for everyone's help!