Fuel Filters On E7 300

[macattack]

i am not too familar with the mack e7 300 engine.

what is the proper procedure for changing the fuel filters on the e7 300 engine. is there 2 filters? and which one is the primary filter?

any other things i should look out for on these engines? its a 1996.

also it looks like the valve cover gasket is leaking is this popular on these engines?

any tips or tricks would be great.

thanks everybody.

[HK Trucking]

i am not too familar with the mack e7 300 engine.

what is the proper procedure for changing the fuel filters on the e7 300 engine. is there 2 filters? and which one is the primary filter?

There are 2 filters - a red primary and green secondary.

Remove both filters, making sure that the gaskets come off along with the filters.

Fill each new filter with CLEAN fuel and put a film of motor oil on the gasket before installing it. Spin each filter on until the gasket contacts the base, then tighten further until snug. Don't overtighten or you could damage the filter, and it would also make it difficult to remove next time.

If your truck has a manual priming pump on the transfer pump (located on the side of the injector pump), pump the plunger now until resistance is felt when pumping, indicating that fuel is being pumped thru the filters and inj. pump.

Start the engine (it may run rough or stall a few times until the air is worked out of the system).

You must prefill the filters as described or it will be next to impossible to get the fuel system "primed up" again.

any other things i should look out for on these engines? its a 1996.

also it looks like the valve cover gasket is leaking is this popular on these engines?

any tips or tricks would be great.

thanks everybody.

Valve cover gasket leaks on the E7 usually happen on the right side, I think the heat from the proximity to the exhaust ports causes gasket failure eventually. If your engine has Jake brakes on it, you'll also want to replace the gaskets between the Jake spacers and the heads while you've got the valve covers off.

.

[sbrem]

If your truck has a manual priming pump on the transfer pump (located on the side of the injector pump), pump the plunger now until resistance is felt when pumping, indicating that fuel is being pumped thru the filters and inj. pump.

Herb, what is the best way to prime an E7 without a manual priming pump?

[HK Trucking]

Herb, what is the best way to prime an E7 without a manual priming pump?

Make sure you pre fill both of the fuel filters, then try to start it up and it should pick up the fuel with some sputtering and missing for a minute or 2.

Don't crank excessively if it doesn't fire.

To prime the system:

Disconnect the fuel return line at the relief valve on the side of the injector pump.

Plug the return line (leave the fitting on the relief valve "open").

Use compressed air to pressurize the fuel tank (a "blow gun" in the filler opening with a rag stuffed around it to hold the pressure in).

Pressurize until fuel flows from the open fitting on the relief valve.

Once this is achieved, reconnect the return line, put the fuel tank cap back on and it should fire up.

Pressurizing the tank without removing and plugging the return line from the relief valve will accomplish nothing, as the pressure will also go back thru the return line and counteract the flow of fuel from the tank thru the supply line.

.

[sbrem]

Thanks! :thumb: