Mack Em 6

[paul 111]

I have been looking on here and diesel garage and found some very useful information about the EM 6 engine from fred and mackattack, great job.

The only question i would like to know does anyone know how to shim the puff limiter properly and the steps involved as ours is very very gutless with puff limiter in

[rhasler]

1. With the puff limiter removed from the pump apply 60 psi to the it and measure the extension of the rod with a depth micrometer.

2. On the front of the pump there is a dimension stamped as "PLE", subtract this dimension from the dimension obtained in step 1

3. Build a shim pack to the same dimension that was obtained in step 2, you may want to add a .010" shim, which will provide a bit more smoke than the factory setting.

I'm not sure of how the pump will be marked for Australia/export, the measurement may be in millimeters or it may be in inches. I am also regretfully unaware of most of the emission settings for such engines, so I hope this much is at least helpful. Is this a true export emission engine or is it set to US regulations?

[fjh]

1. With the puff limiter removed from the pump apply 60 psi to the it and measure the extension of the rod with a depth micrometer.

2. On the front of the pump there is a dimension stamped as "PLE", subtract this dimension from the dimension obtained in step 1

3. Build a shim pack to the same dimension that was obtained in step 2, you may want to add a .010" shim, which will provide a bit more smoke than the factory setting.

I'm not sure of how the pump will be marked for Australia/export, the measurement may be in millimeters or it may be in inches. I am also regretfully unaware of most of the emission settings for such engines, so I hope this much is at least helpful. Is this a true export emission engine or is it set to US regulations?

Now that being the correct way to shim it! This is how I do it Be cause you will be hard pressed to find shims ! limit bimo removed Full head of air release the brakes snap the throtle down Should get a black cloud! Now in stall a 9/16 flat washer behind the bimo as you install it hook it up and repeat the throtle snap should have deminished the smoke by half or more,What I shoot for is just a wisp of gray at throtle snap if you can get this you will have decent pickup and not a hole pile of black!If you set it to bimo specs on the pump you will not be happy with the pick up.

not b a happy camper,.

[theakerstwo]

Now that being the correct way to shim it! This is how I do it Be cause you will be hard pressed to find shims ! limit bimo removed Full head of air release the brakes snap the throtle down Should get a black cloud! Now in stall a 9/16 flat washer behind the bimo as you install it hook it up and repeat the throtle snap should have deminished the smoke by half or more,What I shoot for is just a wisp of gray at throtle snap if you can get this you will have decent pickup and not a hole pile of black!If you set it to bimo specs on the pump you will not be happy with the pick up.

not b a happy camper,.

This is the way i have did it for a few years altho i do drive and add or take away shims as i get the feel that i like. No use in smoke.

[paul 111]

Thanks alot for the replys, you blokes are great, i will give it a shot and get back to you in the next coupla days. Great work

[paul 111]

This engine was bought in Australia about ten years ago, we have two of them and the other one is sitting in shed, meant to be gutless and worn out.Im not sure if this engine is a true export i will look at numbers on pump and let you know, supposed to be a 350 HP, do you guys know how to tell what HP it is because it is very slow when going up a hill with 42.5 ton on, alot slower than a old 350 cat or cummins , even when tipper bins are empty it struggles. Emissions are not too bad over here, just this truck when you get going just pours black smoke out with puff limiter disconnected, i would like to put it back in as this will put fuel in sump, use excess diesel and unwanted wear as yous pointed out.

[rhasler]

fjh and theakerstwo are right, they have suggested a simpler way to adjust the puff limiter. I somehow didn't post the fact that adding a bit more to the shim pack will prevent the puff limiter from interfering with the travel on the rack.

If you can get a certification year from the engine data tag we can probably check to see what pump it should have, at least for US regulations. Of course that's no guarantee that the pump is still calibrated to those setting either.

[Kav]

This engine was bought in Australia about ten years ago, we have two of them and the other one is sitting in shed, meant to be gutless and worn out.Im not sure if this engine is a true export i will look at numbers on pump and let you know, supposed to be a 350 HP, do you guys know how to tell what HP it is because it is very slow when going up a hill with 42.5 ton on, alot slower than a old 350 cat or cummins , even when tipper bins are empty it struggles. Emissions are not too bad over here, just this truck when you get going just pours black smoke out with puff limiter disconnected, i would like to put it back in as this will put fuel in sump, use excess diesel and unwanted wear as yous pointed out.

Hi Paul - Have you checked the boost pressure of the turbo. If your pressure is low, the Puff limiter will cut back your fuel and it wont pull properly. It might pay to check the turbo numbers as I have heard of second-hand motors that were "runners" that had the 350 Turbo taken off and an old 237 turbo put in its place. The 350 motors are usually good performers as they were originally 350 at 1800 rpm, and when you run them at about 2100 rpm they go very well. They will stay with a 400 Cummins all day if they are set right.Regards - Michael.

[paul 111]

Thanks for all the replys, today we just had a new 18 speed roadranger in truck as old one was a 8 speed and only went 90 flat out,not good for engine, done a couple of loads and went back to shed and had a tinker.

The fuel pump is a Ambac Model 300 PLM 450276 ser no 042461 Mack part no. 5163 P2, 22 degrees BTDC.

Now did some looking at old motor in shed as they are supposed to be the same and is a EM6 300, federal family 14, 1988 model could not find a compliance plate on one in truck behind the injector pump, will have to give engine a wash and look for a eng no and source from there.

The helicoil in housing where puff limiter screws into came out so i put a new helicoil in, we have a new round housing which puff limiter screws into but looks like a big job to replace this part as pump needs to be moved back to get in there.

Now the "PLE" no on pump is 1022, is this 1022mm?? I am abit comfused here, I measured with 60 PSI the travel on puff limiter ram,from end of push rod to start of thread housing measured 17.5mm, how do i figure out shim packing from here 1022mm-17.5mm =1004.5mm???is this correct anyone sounds like alot of shims ,i put in with 2 thin washers and left it at that for now prob about 2mm thick.

I checked all intercooler pipes and hoses and replaced one hose which was leaking. The next day or two i will start when cold with fan belts disconnected and check to get a better look at pipes, hoses and intercooler for leaks without the fan blowing all the soapy water everwhere.

I will also check number on turbo as kav suggested and may have to rig up a boost guage in dash.

Took truck for a drive and performed a little better with less smoke but still reckon turbo boost is the problem.

See how it responds with a load on it.

Thanks everybody great job, any other comments or suggestions more than welcome.

Edited November 10, 2010 by paul111

[rhasler]

Thanks for all the replys, today we just had a new 18 speed roadranger in truck as old one was a 8 speed and only went 90 flat out,not good for engine, done a couple of loads and went back to shed and had a tinker.

The fuel pump is a Ambac Model 300 PLM 450276 ser no 042461 Mack part no. 5163 P2, 22 degrees BTDC.

Now did some looking at old motor in shed as they are supposed to be the same and is a EM6 300, federal family 14, 1988 model could not find a compliance plate on one in truck behind the injector pump, will have to give engine a wash and look for a eng no and source from there.

The helicoil in housing where puff limiter screws into came out so i put a new helicoil in, we have a new round housing which puff limiter screws into but looks like a big job to replace this part as pump needs to be moved back to get in there.

Now the "PLE" no on pump is 1022, is this 1022mm?? I am abit comfused here, I measured with 60 PSI the travel on puff limiter ram,from end of push rod to start of thread housing measured 17.5mm, how do i figure out shim packing from here 1022mm-17.5mm =1004.5mm???is this correct anyone sounds like alot of shims ,i put in with 2 thin washers and left it at that for now prob about 2mm thick.

I checked all intercooler pipes and hoses and replaced one hose which was leaking. The next day or two i will start when cold with fan belts disconnected and check to get a better look at pipes, hoses and intercooler for leaks without the fan blowing all the soapy water everwhere.

I will also check number on turbo as kav suggested and may have to rig up a boost guage in dash.

Took truck for a drive and performed a little better with less smoke but still reckon turbo boost is the problem.

See how it responds with a load on it.

Thanks everybody great job, any other comments or suggestions more than welcome.

It sounds like it may not be an export engine. If I'm not mistaken it would identified as an EME6 if it were. The "PLE" number sounds like it is in inches, so you would need a shim pack at least around 15MM.

[fjh]

It sounds like it may not be an export engine. If I'm not mistaken it would identified as an EME6 if it were. The "PLE" number sounds like it is in inches, so you would need a shim pack at least around 15MM.

Thousanths of an inch I would think its an AMBAC Pump Most everything was in Imp measurment!

[rhasler]

Thousanths of an inch I would think its an AMBAC Pump Most everything was in Imp measurment!

Right, the dimension should be in inches. I figure he'll have metric reading instruments so I converted the PLE dimension to millimeters, subtracted the extension of the cylinder, and added approx. 7MM to prevent interference with the rack. Check my math though, it's early still.

[paul 111]

Any one know about these turbo numbers on this motor, i have a number xjm0024 466220-9001 just wondering if it is the correct turbo for the 300 HP engine