Hey guy I was adjusting the valves on my recently purchased 72 914 with 1.8 swap. The engine is incredible loud and I can only assume it is the valve train. (just loud clatter not deep enough to be a rod or wrist pin knock) I pulled valve covers and noticed the number 1 intake rocker had a strange feel to it. Upon closer inspection the lifter tube has been slightly crushed and was not allowing the rod to correctly align with the rocker causing a lateral load on the rocker compressing the spring slightly on the rocker shaft.
I removed the push rod to inspect for damage and noticed a ring(approx. 2-3mm deep) machined into the aluminum just past where the retainer spring would contact it. I pulled out the exhaust push rod to see if it had the same ring in it and it indeed does. After wondering what it is for and scouring the web for pics of different push rods I have come to the conclusion that mine are the odd man out.
Has anyone heard of anything like this or seen any?

One more push rod related question.......I read I can install the spring loaded type1 push rod tubes in my motor. Can anyone confirm this. I need to change the tube and dont really want to drop the motor right now

The notch is because someone didn't get the retaining wire seated correctly. The soft aluminum rod rubbed on the hard steel retaining wire, wearing a notch in it.

You might be able to use the spring-loaded tubes, but there is no need to. Instead of being sandwiched between the head and case like on the Type I (or 911), the tubes slide through the head into the case. They are relatively easy to replace with the engine in the car.

You just slide the tube halfway out, then drop the inboard end down away from the head, and slide it all in. The tube is out, and you can replace the seals.

--DD

It's rare that you ever need to replace the tubes, unless they are bent or damaged. The O ring seals, they are known to leak when bad or marginal.

About 25 years ago when I did my first rebuild, I made the same mistake with the wire retainer. Lucky for me (and you too) I discovered the problem before it broke the pushrod. You just need to replace those damaged push rods. Since you've got the rockers off though, I'd replace the PRT O ring seals. Do a search on this site and you'll get some good info. Lightly lubricate the seals with Locktite 105, which will help seal them, but don't use RTV.

Thanks for the input guys I am ordering new push rods and a couple stock lifter tubes this afternoon

You CANNOT use T1 pushrod tubes in a T4. Length, diameter, method of securing, overall design. In fact, because of the design, a spring loaded tube wouldn't work. I often straighten a bent or dented tube by driving a 14mm deep socket through it

The Cap'n

If it looks like this is from the retention spring.

I replace tubes all the time, but only to make them pretty. Cleaning up old ones gets expensive and new ones at $6 each. So new is cheaper then cleaning and painting/plating.

Perry,

I went to look for locktite 105 and I couldn't find it at my FLAPS nor Home Depot, I did a Google search with no results. was that a typo?

I have been using Dow Corning® 111 Valve Lubricant and Sealant.
It is s thick silicon based grease, has a wide temperature range.
Does not take much.
Don't know where to get it now, been using a tube I got a decade ago.
Jim

Sorry for my bad memory, it's Loctite 565, and the small tube will work if your stingy. IIRC it's like $10 for a 1 oz tube.

Clean the PRT bores and make sure there's no gouges or deep scratches.