Got my battery changed out so that I could track down my wiper, blower motor and radio gremlin when I noticed over half of my injector blocks were cracked. I have a new set on order but wanted to know if it was safe to drive the car until the new set comes in.

my '82 turbo blocks would leak when cracked. Not sure if it's a problem with non turbo. Make sure you don't over tighten the new ones when you replace them.

It shouldn't be a problem. The screw holes are still intact and will hold the pieces in place. Like Darrel said, they don't need to be very tight. Once the screws have pressed the injector seal down in to the hole, and squeezed the insulator and metal top piece together and down to the manifold (no gaps), there's little benefit to being tighter.

I think my blocks were cracked when I replaced them, and they didn't leak. There's an O-ring that seals the tip of the injector in the manifold's hole. Assuming you're not running a turbo or supercharger, there will always be a vacuum inside the manifold, so IF there is any leakage of any sort, it will be from the outside to the inside. Thus any stray fuel would be kept inside the intake manifold. So in my non-expert estimation, there is nothing unsafe about your cracked insulators.

When I change the blocks, will I have to replace the injector o rings ?

I don't know that you'll HAVE TO change them. I think mine came off intact and could, in theory, be re-used. However, I think it would probably be a good idea. I found a complete O-ring kit on ebay for maybe $9 at the time.

Thanks

I've just spent the last couple of weeks looking at injectors and seals and mounts. I've re-used all of the seals before, both the small ones and the big ones, but wold probably not re-use the bottom ones again if I ever have a choice in the future. The mounting system is designed to compress the bottom seal in to the manifold to a specific distance. Then it sits there getting baked over time and tends to lose its elasticity and take a set. So it won't have the same squishiness if re-used, and might not seal completely. If they still seem rubbery and elastic, they'll probably be okay. Looking at your picture, I would guess that they'll be rock hard.

The big top rubber ring though, is just a vibration insulator and locator. I would reuse that one unless it was rock hard. they're a pain to get on and off.

When you pull the injectors make sure the seal doesn't stay in the manifold. You might think you lost one but it will still be stuck in the hole.

And when you're removing the fuel rail don't forget about the mounting bracket to the intake manifold bolt. It's hard to see when standing at the fender, it's under the rail, and many rails have been bent by people pulling before taking that last bolt out.

Edited April 27, 201410 yr by Zed Head

The injectors, blocks and o-rings are only a couple years old. I only hope I can leave the injectors connected to the fuel rail, I will get a set of o-ring on the way also

I noticed the newer hex head screws. That may be how the holders got cracked, too much righty tighty.

Just replaced mine, see post with part numbers below:

http://www.classiczcars.com/forums/fuel-injection-s30/51835-hot-start-issue-efi-who-has-who-doesnt.html#post454170