Dynatard

[Old Dog67]

I bought a 97 ch with a mechanical e7 350. The truck had factory Dynatard but the engine was replaced due to severe over heating. The replacement engine was not equipped with Dynatard but the truck came with the old engine. My question is will I have to change the entire rocker assembly or can I remove plugs and screw in Dynatard solenoids? Yes I will run the overhead while in there. I’m very aquatinted with Jake’s but never fooled with Dynatard.

[fjh]

1 hour ago, Old Dog67 said:

I bought a 97 ch with a mechanical e7 350. The truck had factory Dynatard but the engine was replaced due to severe over heating. The replacement engine was not equipped with Dynatard but the truck came with the old engine. My question is will I have to change the entire rocker assembly or can I remove plugs and screw in Dynatard solenoids? Yes I will run the overhead while in there. I’m very aquatinted with Jake’s but never fooled with Dynatard.

Does the engine have the right rocker assembly for dyntard ! if the dynatard cam is installed you can use the dynatard rocker assembly's to complete the process ! Just installing rockers is half of the equation U can also get jake assembly's to fit this engine!

[67RModel]

Quick question: Is a Dynatard the exact same mechanical principle as a Jacob's compression brake with Mack's name on it? I have heard from several guys that they aren't as "good" as a Jake? I never asked what they meant by this. Reliability? Cost? Braking Power? what are the differences if any? Thanks.

[mechohaulic]

engine brakes act on same principle;; hold the exhaust valves open at compression stroke.  actual hold back is from cyl not creating a power stroke. the noise is from the compression/ power in cyl going out the exhaust. a jacobs engine brake is much better then early dynatards.  the jacobs is an add on - new exhaust adjusting screws and spacer. the dynatard is a built in from cam to pushrods and different rocker assy. first dynatard were junk. bent the exhaust push rods : many were changed over to the updated solid rods. oil pressure to me was more critical with the dynatards; that little rocker cyl did all the work. jacobs had it's down falls but fewer.

[mechohaulic]

5 hours ago, Old Dog67 said:

I bought a 97 ch with a mechanical e7 350. The truck had factory Dynatard but the engine was replaced due to severe over heating. The replacement engine was not equipped with Dynatard but the truck came with the old engine. My question is will I have to change the entire rocker assembly or can I remove plugs and screw in Dynatard solenoids? Yes I will run the overhead while in there. I’m very aquatinted with Jake’s but never fooled with Dynatard.

unlike a jacobs which is an add on with little changing a dynatard  is totally  different ; it is a built in. meaning the rockers are different , exhaust rockers have solenoid assy built in ;not just changing adjuster . when adjusting a dyna make sure you push down on the rocker to empty all oil (other way tighten adjust to compress oil out, then back off and process with adjustment) cam has to be right one 

[mechohaulic]

forgot ;; the valve covers themselves should be different also.  "pregnant " hump where exhaust valve is noticeable from outside 

[Old Dog67]

6 hours ago, mechohaulic said:

forgot ;; the valve covers themselves should be different also.  "pregnant " hump where exhaust valve is noticeable from outside 

I have the valve covers that came on the burned engine and they don’t have a hump on them. Also the dynatard solenoids go directly on the rocker shaft (1 per shaft). My rocker shafts have a plug in them where the solenoids go.  

[BOBWhite]

Do you have a picture of that hump? I didn't know there was a difference in valve covers besides maybe an electrical terminal for the solenoid's. Maybe the 2 valve stamped steel covers had a hump but I can't say Ive seen a difference in the 4 valve cast aluminum covers. I know someone will know for sure. 

[fjh]

1 hour ago, BOBWhite said:

Do you have a picture of that hump? I didn't know there was a difference in valve covers besides maybe an electrical terminal for the solenoid's. Maybe the 2 valve stamped steel covers had a hump but I can't say Ive seen a difference in the 4 valve cast aluminum covers. I know someone will know for sure. 

I believe the 4 valve cover will fit either or !

[mechohaulic]

the "hump"covers go back to early dynatard days; don't thing they were even 4 valve. EACH exhaust rocker had a solenoid  if I can remember. 7/8= 15/16 thin lock nut, a tool basically a flat scrapper was used to adjust valve . another very important step I forgot. the early dynatards  valves  HAD to be adjusted in proper order. on many non-dyna  engines if say #1 cyl was at TDC a random number of cyl could be adjusted, a complete valve adjust could be done in 2 spins.  with the EARLY  dynas  the front crank damper had the timing marks which had to be followed.  a cyl adjusted would have an exhaust cyl  that appeared "way out "of adjust when eng rotated. cam lobes . challenging times after many new dyna engines came in for rocker push rod up dates and no one was there to explain the double lobe cam.  adjust a cyl rotate for next cyl and previous cyl exhaust way out of adjust. didn't know it was made that way. rotate back to the cyl adjustment was perfect. in most responses i post it's based on the very early days . 

[mechohaulic]

15 hours ago, BOBWhite said:

Do you have a picture of that hump? I didn't know there was a difference in valve covers besides maybe an electrical terminal for the solenoid's. Maybe the 2 valve stamped steel covers had a hump but I can't say Ive seen a difference in the 4 valve cast aluminum covers. I know someone will know for sure. 

steel covers : old R  model etc era   ; not alum  new style .had solenoid  "hump" in valve covers . 3 humps per cover  = one for each solenoid. Dang::am I really that old; LOL.  i'm not that old - technology is changing toooo fast. sounds better.