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Knocking sound - Printable Version

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RE: Knocking sound - Rawze - 08-10-2016

Let me know when you get it by there, -- remind me .. I don't mind seeing what it is sounding like and taking a look at it, perhaps bring it by my place or I can take a ride over there. It could be a number of things.


RE: Knocking sound - overshot - 08-10-2016

(08-10-2016 )Rawze Wrote:  Let me know when you get it by there, -- remind me .. I don't mind seeing what it is sounding like and taking a look at it, perhaps bring it by my place or I can take a ride over there. It could be a number of things.

Sounds like a deal. Hopefully I'll be freed up on the 22nd and come by your place.


RE: Knocking sound - snailexpress - 08-10-2016

i have absolutely the same knocking on 2250.
Thought it's a front gear to compressor/fuel pump.
Please post what you find.


RE: Knocking sound - overshot - 08-10-2016

(08-10-2016 )snailexpress Wrote:  i have absolutely the same knocking on 2250.
Thought it's a front gear to compressor/fuel pump.
Please post what you find.

Will do


RE: Knocking sound - Hammerhead - 08-10-2016

Can you more clearly define the knocking sound?
When you say "goes away when the Jake is on, are you sure or is it being masked by the noise of the Jake?
Do your Jakes "instant on full pressure" or do they "build pressure in a second or so"?

I reffered to mine as a "tapping" that also went away when the Jake was on. The reason mine went away when the Jake was engaged was because it was worn detent holes in the rocker shafts. The check valves were also worn, and the Jake springs had compressed a little over 1/4" at about the same mileage. What happens is the Jake rocker does not get held into the detent position and bounces (taps) off the cam.
This is why I believe we should be changing out the springs in the Jake rockers every 200,000 (when most guys run an overhead adjust). They just get weak over time and lead to wear, and I'm convinced that keeping good springs will extend the life of both the check valves and the rocker shafts.

edited to add...this is the link to my corrective action to my sound.
http://rawze.com/forums/showthread.php?tid=557
Key posts are;
6- shows the old and new shafts so you can see the wear on the detent hole
8- advise right from Mr Hagg about the springs, cause I dint know enough to go that far at that time. When you get to that mans shop, shake his hand and say Thank You for me please
14- this is the part number lists for the shaft (front and rear), check valves, and springs
17- an exploded view of one of the shafts and pieces.
18- old spring beside a new one to see the compression over time reduction of spring length
25- a complete list of the results of all the work I did, including the Jake service. I still stand by the statement of "You will not know how badly your Jakes have degraded over time until you complete this service"

Good luck, and keep us informed...


RE: Knocking sound - overshot - 08-11-2016

(08-10-2016 )Hammerhead Wrote:  Can you more clearly define the knocking sound?
When you say "goes away when the Jake is on, are you sure or is it being masked by the noise of the Jake?
Do your Jakes "instant on full pressure" or do they "build pressure in a second or so"?

I reffered to mine as a "tapping" that also went away when the Jake was on. The reason mine went away when the Jake was engaged was because it was worn detent holes in the rocker shafts. The check valves were also worn, and the Jake springs had compressed a little over 1/4" at about the same mileage. What happens is the Jake rocker does not get held into the detent position and bounces (taps) off the cam.
This is why I believe we should be changing out the springs in the Jake rockers every 200,000 (when most guys run an overhead adjust). They just get weak over time and lead to wear, and I'm convinced that keeping good springs will extend the life of both the check valves and the rocker shafts.

edited to add...this is the link to my corrective action to my sound.
http://rawze.com/forums/showthread.php?tid=557
Key posts are;
6- shows the old and new shafts so you can see the wear on the detent hole
8- advise right from Mr Hagg about the springs, cause I dint know enough to go that far at that time. When you get to that mans shop, shake his hand and say Thank You for me please
14- this is the part number lists for the shaft (front and rear), check valves, and springs
17- an exploded view of one of the shafts and pieces.
18- old spring beside a new one to see the compression over time reduction of spring length
25- a complete list of the results of all the work I did, including the Jake service. I still stand by the statement of "You will not know how badly your Jakes have degraded over time until you complete this service"

Good luck, and keep us informed...
Thanks for the link Hammerhead.
No, it doesn't knock when using jake.
It only knocks during acceleration.
And no the boost pressure does not immediately jump to 32 psi when jack is applied. It does have immediate psi of about 10 psi and works it way up to 32 psi in short order.
I don't thinks it's a top end tap. But hey, what the hell do I know.


RE: Knocking sound - Dcolumbia - 08-14-2016

Mine did that, turned out to be a bad rocker rod, detents for the Jake's won't hold at about 1200 rpm. Pull the valve cover and idle the engine up. You can watch the rocker just take off and start knocking on the side of thead.


RE: Knocking sound - overshot - 08-21-2016

UPDATE****

seems my issue was a fueling and timing thing. it was not a bad or detrimental issue.
Rawze & Vin installed the new updates today and things smoothed out and quited down.
Though it still makes some knocking noise, Rawze says its normal for this engine and HP rating to do that. And, that there's nothing to worry about.

So fellas if your engine is making a funny or unusual noise get it checked out just to be sure and get the latest updates.

Rawze & co. work hard and constantly to improve that they have built. I seen today that it's not just a one and I'm done thing.

Thanks Rawze and everyone else on here.


RE: Knocking sound - Hammerhead - 08-21-2016

That's great news!