I took the valve guides out of our '88 190E. How does one go about putting the new ones in without damaging them? Seems as though they will be awfully tight going in. Any suggestions are appreciated.
Thanks in advance.

Kyle

valve guides
 

The way I do it is put the head on a 2 burner hot plate and heat the head pretty hot. Usually just as it begins to smoke a little I'll remove the head from the hotplate and immediatley hammer the guides in with an air hammer with a valve guide tool. This might sound crude but it works. Very seldom do I have to ream the guides only sometimes just the hammer edge has to be cleaned. Be careful not to knock them in to far I always mark them before installing them as not to install them too far.

If you freeze the guides in addition to heating the head it will help also.

If you are fast enough

The guides are a interference fit in the head casting. The head will have to be heated in an oven to a uniform temp. The guides are usually pressed in to the casting. This is best left to a machine shop with the correct equipment. Generally not a DYI type of task..

thanks guys, I think I am going to take jeffsr's advice and leave it to a machine shop.

If the guides are an interference fit, how did you get them out?

Pounded with a socket and hammer.

One needs to be careful with aluminum heads. The casting is not very thick in the valve guide area and can be fractured with too much hammering. The head needs to be heated and the guides pressed or pulled out. Same is true for reinstalling new ones. The interference fit is necessary to keep the guides in place while the engine is operating over a normal or occasionally, abnormal range of temperature.

Thanks for the responses.
It is out of my hands now. I dropped it off at a reputable machine shop to have the seats cut, surfaced, cleaned, guides reinstalled and valves & springs put back in. Hopefully I will get it back for the weekend. Thanks again, this forum is better than all the manuals combined.

Kodiak

Kodiak,HOw much did it cost you(machine shop)?


Ron

Like I said, cut seats, surface face, install valves, install valve guides and clean, they quoted me $170. We'll see when I pick it up. I will let you know for sure.

Just picked up the head. Wow, It's like new. I will be posting pix at: http://www.users.fast.net/~effort/mb

The total price was $162