Fitting pop up valve for air box

[Ivelosttheplot]

Hi

ive just ordered a pop off valve for my 76 cis engine.

engine has just been fully rebuilt so thought the builder would have fitted this valve , but ha ho

it arrived without a template but I should be able to sort that

video’s vary a bit but I’m assuming after cutting the hole with a 51mm hole cutter that you need to trim the ribs down so that the valve sits flush on the box, some I’ve seen sit on top of the ribs which seems totally incorrect 

also the best glue to use ? Was thinking of j b weld suitable for plastic ? Available via amazon 

 

regards Keith 

 

 

[Jonny Hart]

Have you actually tested your airbox for leaks?  

[Ivelosttheplot]

No

bit it looks ok, no cracks or signs of damage

i now have a Porsche engineer assisting me or me assisting him, with putting the engine back in the car next week because  I don’t  have a ramp so will thoroughly go through with him

just got to put new injectors in and it should be ready to re install

after fitting the pop up valve of course

painfull this engine has been as the builder is very experienced but painfully slow , this new engineer is also an air cooled guy so hopefully ill getting on with it.

then onto suspension set up 

 

cut out the airbox ribs for the pop up valve ?

what epoxy to seal in ?

regards Keith 

 

[Phill]

I thought there used to be instructions on Matt’s website @Type911 ?

If I can remember that far back I’m fairly sure I cut the ribs down, as you say you can’t get it tight and flush without doing that. The air box is made of “difficult” plastic so you have to make sure you prep it really well and then use some two part epoxy. As an aside, when we fitted the arches on my sons Golf we found nothing would stick to them as they are made of polypropylene. Even tiger seal wouldn’t work or even specific polypropylene adhesives. Our solution was to sand the surface and then coat it with superglue in the areas we needed to glue. We then used polypropylene glue on top of the superglue “primer”. This worked very well.

[Type911]

Yes, instructions and template are on our listing for the valve

Ribs need to be cut off so the valve fits completely flush, a dremel is ideal, I used Silkoflex, as Phil says, roughen up the area first

[Ivelosttheplot]

Thanks guys

ill be putting the valve in this week 

subject to a ramp free the engine goes in early next week

cheers again

keith

[Ivelosttheplot]

Just thought I’d update on the pop up valve.

it was an easy fit job really

after setting its position I drilled a 6mm pilot hole and marked the area to be removed. You actually have to remove a few ribs to get the valve to sit flat. I used a 53mm hole cutter from Amazon and almost cut through the plastic , this stops bits falling inside, stuck a hoover on and removed all bits then on the final break through had someone hold the hoover on.

I blocked the hole carefully then using a dremmel removed any ribs stopping the valve from sitting flush.

a good helping of jb weld for plastic and it’s a perfect fit and no debris.

next day it was solid and ready to go.

all in all 45minutes.

👍