What is causing so much build up on my /6 valves ?

[DartThis74]

After spending the whole day trying to take a broken bolt out of the exhaust manifold and replacing old manifold gaskets, I found some really nasty build up inside of the intake ports and on top of the intake valves. What is a primary cause of this ? If the engine is running to rich could this be a factor ? Hopefully you can see some of what I am referring to in the pictures. Just couldn't get a good angle on the ports and get good lighting at the same time.

Thanks for any suggestions or help !

 

[805moparkid]

i just went thru this in my head it was because the guides were to loose

 

[DartThis74]

some more photos, hopefully better.

 

[DartThis74]

How would loose guides cause build up of gunk in the intake ports only. Is it keeping the valves open constantly thus allowing some exhaust to flow back into the intake mixing with the incoming fuel causing the build up ?

 

[805moparkid]

How would loose guides cause build up of gunk in the intake ports only. Is it keeping the valves open constantly thus allowing some exhaust to flow back into the intake mixing with the incoming fuel causing the build up ?

the clearance between the guide and the vavle get loose due to poor machining or worn out, then excessive oil can get suked into the intake port causing build up...

hope that made sense becasue we dipped into the bottel of jack otonite!

 

[DartThis74]

That does make sense. I guess that can also explain the burning of oil. I usually have to put a new quart of oil in every two months. But it's every single intake port. I guess the wrong guides were used huh for those ?

Just a side thought, would I be able to tell if they are loose if I could reach in with some needle nose pliers and see if it has play in its movement ?

 

[67Dart273]

If they're not terribly loose, get a knurling kit, and put teflon valve seals on at least the intakes. These are not "normal" seals, they require a cutting tool which cuts down the height/ diameter of the OD of the guide, then the seal fits tight over the guide.

This is just an example photo, which came from this page:

http://mgaguru.com/mgtech/engine/ch202.htm

but shows you what some of these look like. Sealed Power, TRW, some others sell them

Depending on the engine, you'll need the proper cutter to trim the OD of the guide:

A typical knurling kit is essentially a "wierd tap" which you screw down through the guide, which raises material as it goes. The second part of the tool is a reamer/ burnishing tool which reams the disturbed material back to size.

Some people swear with, some swear at knurled guides. They do work, at least on engines that aren't expedted to live for 200K.

 

[805moparkid]

If they're not terribly loose, get a knurling kit, and put teflon valve seals on at least the intakes. These are not "normal" seals, they require a cutting tool which cuts down the height/ diameter of the OD of the guide, then the seal fits tight over the guide.

This is just an example photo, which came from this page:

http://mgaguru.com/mgtech/engine/ch202.htm

but shows you what some of these look like. Sealed Power, TRW, some others sell them

Depending on the engine, you'll need the proper cutter to trim the OD of the guide:

A typical knurling kit is essentially a "wierd tap" which you screw down through the guide, which raises material as it goes. The second part of the tool is a reamer/ burnishing tool which reams the disturbed material back to size.

Some people swear with, some swear at knurled guides. They do work, at least on engines that aren't expedted to live for 200K.

i had a head knurled and it lasted a little over 10k miles... just spend the little extra and do it right... have the head decked to up the compression, install new guides with positive lock seals...

 

[66cuda]

LOL your slant 6 has a poor diet and obviously has too much BAD Cholesterol cloggin its arteries ..... fee it some of these cholesterol reducing drugs and things will be ok
Altoprev (lovastatin)
Crestor (rosuvastatin)
Lescol (fluvastatin)
Lipitor (atorvastatin)
Mevacor (lovastatin)
Pravachol (pravastatin)
Zocor (simvastatin)

Once the cloggin is cleaned out ...keep it away fom the fast foods and pizza

 

[AussiePlymouths]

OK 66cuda, but what will he do if they keep on upsizing him???

 

[66cuda]

There comes a point in every grown vehicles life where decisions have to be made......... if continue consumption of high cholesterol foods is cloggin him up, then he needs to back off......and especially back off the UPSIZING to Monster Fries, Monster Coke and double cheese burgers!!!!