83 Cab QV - Timing Belt broken, again...

Thanks for the advice. Plan on changing the oil and filter 500 miles after I get things back together. I like the Mahle OC-61 filter for it's quality and extra capacity. Not familiar with the Agip oil, but expect that's what it delivered with.

 

Got the diagnosis today on the QV head where valves contacted pistons. The heads are fine and the valve guides are within serviceable limits for the mileage on the car. No chaffing on the valve stems and all of the valves removed without complications.

This is a tough little engine.

Each of the valves has a 1 to 2 degree variation near the tulip end and all will replaced. Thank you Crowndog! You are awesome.

 

Have elected to use the viton valve seals for their superior sealing power. They may not last quite as long as the teflon type seals, but I believe that they do provide a better oil seal.

 

Found the viton original seals at Superperformance. Seems they are getting harder to obtain. Some delays through Holidays, but head work should be completed as soon as the beautiful Air Injection Plugs from Ricambi are installed. Thanks Daniel for your help!

 

Good idea. Thank you.

 

Gentlemen,

I have the greatest respect for your opinions and expertise. Suggestions for replacing the guides at this point in time are still useful as the heads have not actually been reinstalled. I guess I would like some confirmation of the procedure for replacing them. Not a precision technical answer as experts will do that, but more of a general discussion.

The "should the guides be replaced?" question was discussed near Thanksgiving (late November). The conclusion reached at that time based on previous experience and careful inspection was that they should be fine. The post that they cannot be "crack tested" while in the head is well understood and logical of course.

Here's what has been done in December. All of the valve components have been thoroughly inspected (except the potential of cracked guides). The valves have all been replaced in the "contact" head. Faces and seats have been ground and matched. Original viton type seals installed as a preference over the teflon seals as this engine has 66000 miles on the guides and I believe they will offer somewhat superior oil sealing ability. Original air injection nozzles have been removed. Head and block decks have been set to "true".

I have zero experience with these cars. Other than a complete round of routine fluid changes and about 100 miles actually driving the car, my suite of experiences are an abundance of waiting and budgeting to tackle my current project, cleaning everything I can get to, and many "while you are in there" activities with the engine out.

Therefore, I must rely on you all (I am from Texas), my mechanic, and others who have real experience. I sincerely appreciate your observations, encouragement, opinions and suggestions. I solicit your advice. Please feel free to PM me if you would care to share some of your personal experiences in a "non-public" way.

If I understand it correctly, replacing the guides would entail specialized machine work and tools, new guides of course, replacing the valve seals again, refacing the valve seats again after the new guides are installed, and a complete shim and lash adjust cycle once completed.

At last, I have a few questions. A reminder that my decision to do the engine out procedure was to inspect both heads and to facilitate cleaning and rubber replacement tasks needed due to the age of the 1983 car. Both heads have been serviced.

If I elect to replace the guides on the "contact" head, should I just go ahead and do the other one too?

Has anyone experienced cracked valve guides in their "contact" scenarios? To date, most of the feedback I have received on this has been encouraging that the guides should good.

What's a reasonable cost for an experienced shop to replace valve guides?

Thank you in advance for your thoughtful and kind consideration.

 

Thank you. Had no idea only $400 labor per head. Expecting much more.

I am good on "no rotation". The engine has not been rotated at all since head removal.
I am good on "no skim". The heads are "true" to a max variance of .001

I am prepared to ensure there is no sort of resurfacing. Will write "Do NOT resurface" on the head deck with a Sharpie and personally speak with the technician.

Now to get some quotes on this work in the Houston and Dallas areas.

 

Nick is providing bronze manganese guides.