# CAV dpa injection pump



## Rstifle68 (10 mo ago)

Gentlemen, I’m desperate for help. I rebuilt my Perkins 3 cylinder diesel on my Massey Ferguson 135 tractor. It has been a smooth process until now.

Where I’ve been getting a lot of conflicting information is timing the injection pump to the engine. I was under the impression that what I needed to do was simply hand turn the engine over to 24 degrees BTDC and set the injection pump on letter “G” and everything would be good.

Well, unfortunately the slotted shaft of the injection pump and the pegged timing gear will not match up. I’ve tried everything possible but nothing works!!!

Does anyone know the proper procedure in timing these two critical elements????

I would really appreciate any help on this problem……

Thanks Rick


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## pogobill (Jan 31, 2012)

Welcome to the forum. I can't really help you, but Just thinking that, could you be out 180 degrees on your TDC?


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## Rstifle68 (10 mo ago)

I just re re checked and I’m on the compression stroke. Like a fool I didn’t write down what the pump was set at when I took it off!! Lesson learned!!!


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## Fedup (Feb 25, 2014)

I have to wonder where you got that "impression" about 24 degrees and the letter G? I'm also wondering what all you did during the "rebuild"? A complete engine strip down, or an in frame "rings and bearings" overhaul? If it was the strip down version, then at some point you had to set the timing gears in place with all marks in time, right? If the other, then you never messed with timing gears so they are as they were before (right or wrong), correct? 

Was anything done to the pump while the engine was apart? If not, there should be no problem with just putting it back where it was. My experience with that engine has never caused me to worry about flywheel timing marks. If the timing gears are indeed all correctly in time, then put the pump onto the gear so the roll pin and slot match. Set the scribe mark on the pump mounting flange to match the one on the inner timing cover and move on. Why can you not do that?


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## Rstifle68 (10 mo ago)

I got the information I listed from reading everything I could find on the Massey 135 with a 3 cylinder Perkins. I also watched endless hours on YouTube. 

What I did was perform a “refresh” on the engine. New pistons, rings, bearings and a valve job. I also rebuilt the CAV injection pump. I had no choice there!

Everything went fine and had no real problems until now.

In a perfect world I would have written down the letter on the pump but I’m a rookie!!


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## thepumpguysc (Jan 25, 2015)

What’s the inj pump #.??


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## Rstifle68 (10 mo ago)

The pump no is RW52


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## thepumpguysc (Jan 25, 2015)

The 1st line on the np..
3233F...


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## Rstifle68 (10 mo ago)

Yep that right. The entire number is: DPA 323 0190

SET RW52/800/6/2160


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## thepumpguysc (Jan 25, 2015)

I’ll check the specs in the AM.


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## Rstifle68 (10 mo ago)

Thanks I really appreciate it. I’m sure your going to find that the pump is set at G and the flywheel is set at 24 degrees BTDC.

mill be checking my phone tomorrow……

thanks again…..


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## thepumpguysc (Jan 25, 2015)

Unfortunately the pump specs don’t give a letter designation or an engine *..
If u think it’s G.. # 1 cyl is outlet W..on the pump..
Apply air to outlet W and rotate the drive in the correct direction of rotation..
Looking at the pump from the drive end, rotate the drive CLOCKWISE slowly until the drive stops..
Then look in the side and see what letter is there..
If the pump is supposed to be letter timed.. there will b a flat on 1 ear of the big c-clip..
R u SURE u have the correct rebuild manual.??


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## Rstifle68 (10 mo ago)

Wow! I’m not sure just what you mean. The letters in the head range from A to H. So I’m not sure what you mean by apply air to outlet W.

I’m wondering if I have to retime the dame thing!
Anyway I want to thank you for looking and your advice.

Rick


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## Hacke (Feb 22, 2011)

Attached manual snippet shows "E" instead of "G"?


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## thepumpguysc (Jan 25, 2015)

The head, where the lines hook to the pump is marked w letters.. probably U, V, W.. in a clockwise rotation..

lemme ask u.. when u took the pump apart.. did u take the head & rotor. apart.??
If yes, u might have put it together wrong.??
Look inside the side cover.. the letters on the rotor should be upside down..


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## Rstifle68 (10 mo ago)

I think you’ve solved my problem. The pdf attachment you sent me clearly shows E which I was able to get quite easily. With E showing in the side viewing port the key way meets perfectly with the peg in the timing gear. So that’s what I’m going with.

Any last recommendations??


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