• Thank you for visiting HeavyEquipmentForums.com! Our objective is to provide industry professionals a place to gather to exchange questions, answers and ideas. We welcome you to register using the "Register" icon at the top of the page. We'd appreciate any help you can offer in spreading the word of our new site. The more members that join, the bigger resource for all to enjoy. Thank you!

CAT 3304-Timing the Injector Pump

tctractors

Senior Member
Joined
Oct 9, 2007
Messages
2,412
Location
Worc U.K.
Bryant, it is possible to spill time this engine with the fuel pump that you have fitted, I have done this task a few times when I have not had my lock plate, this is via a timing disc (bit of plastic) that is of no weight that I always keep in my chariot, I know its not an issue now that you have the correct tooling but it not a hard task to cope with if you have a bit of plastic, anyhow the learning curve is on full flow for you, so please dont be slow to ask about anything that you are not sure about in future before you pull things to bits, as 2 grind marks on the drive gears would possibly have saved you a few coins, oh and on the spill time thing the 3304/6 does have the TDC pin point, so with that set and the disc poked on the front of the crank and fuel in the tank its not hard as even a dummy like myself can cope, it helps to have the throttle control off the stop position though!!!

very pleased that things worked out well tctractors

p.s. my lock plate also fits the D8H/K compact pumps as I drilled it to fit and sold my D8 lock plate, so 1 tool fits all (sort-of)
 
Last edited:

kshansen

Senior Member
Joined
Mar 11, 2012
Messages
11,165
Location
Central New York, USA
Occupation
Retired Mechanic in Stone Quarry
oh and on the spill time thing the 3304/6 does have the TDC pin point, so with that set and the disc poked on the front of the crank and fuel in the tank its not hard as even a dummy like myself can cope,

A little more info? Is there a spec listed for how many degrees BTDC the injection starts? Guess I should just look in SIS, but hey I'm feeling lazy:D
 

tctractors

Senior Member
Joined
Oct 9, 2007
Messages
2,412
Location
Worc U.K.
kshansen, if you think I keep that data in my hollow head you are giving me a bit to much Cred' but I would have this detail in my heap of CAT tech/service books, the heap would be heading towards the 1 ton mark, so its a bit of a rummage to sort through them all, they start at the 20/22 and the 60 gas all the way through to the High drives, but anyhow you sound more interested with how you find the Degree off the front crank, well a fool can do this easily with a bit of welding wire or rod a clamp and a timing disc, my disc by the way is Motor Bike spec from my BSA and Norton days and is about 180 -200 mm Dia' after you poke the TDC pin in its holeyou stick the disc to the front pulley with a bit of tape in any position that gives you the easiest view as you only need a few of the numbers and it makes no odds what number is visible, then you clamp on the wire to the bit that does not turn like the Chassis for instance, then bend the wire to point to any number/position on the timing disc, then you need to do that thing with your fingers to work out how many marks/deg' you need to turn things back, it sort of gets things done and I will say its a lot easier to spill time a D342 (D8 motor) but by now I think you are on track with this endeavour. tctractors
 

kshansen

Senior Member
Joined
Mar 11, 2012
Messages
11,165
Location
Central New York, USA
Occupation
Retired Mechanic in Stone Quarry
That task is way above my pay grade.

Actually a pretty easy method, if, one has a spec. on the degrees BTDC injection is to start. I fully understand the methods to measure crank angle and TDC, anyone else familiar with setting the timing on a Cummins small cam? Real fun doing the VT1710 or KT1150 with the offset keys and pressed on cam gears! Done many Macks and IH 817's with Robert Bosh or American Bosh pumps. Most of them were done with air pressure watching bubbles in a jar of fuel oil.

I did spend a little time on SIS looking for a timing spec for 3304 or 3306 engines with no luck. One problem with using the timing tool from Cat is it always depends on the condition of the parts in the injection pump and the skill of the person who adjusted those parts on assembly. Where "spill timing" would by-pass all that, assuming all cylinders were the same. With a little effort one could take it one step further and check each cylinder to see if there was one or more out of whack.

Then this is not really helping Bryant, sorry for rambling on Bryant!

Hope that 3304 is purrrrring like a Cat should!
 

tctractors

Senior Member
Joined
Oct 9, 2007
Messages
2,412
Location
Worc U.K.
kshansen, on the Cummins motors I get plenty of them to fiddle with, the 1710 and the later 28 with the revision on the firing order etc, the stepped woodruff key and all those shim things (gaskets) on the cam roller box's make any 855-14 L tough going to the simple 3306 with its basic engineering, we used to have a few Mack trucks here in the U.K. running usualy Low loader or Cattle Float, they took some hiding on our hills with rear axle U bolts needing a re-think but the rest held up reasonably well, anyhow I do have the Super spec book some place with all the targets you need to meet on the early CAT engines, I have posted pictures before in shop talk of big /small cam 14 L and 1710 vta 28's that I have pulled to bits, then as you said its not realy helping Bryant the owner of a new 4"3/4 bore lock plate much with our ramblings.
always happy tctractors
 

D6 Merv

Senior Member
Joined
May 10, 2007
Messages
653
Location
Coromandel Peninsula. New Zealand
Occupation
Self employed bulldozing contractor with a D6D D4E
All the ones I spill timed like this I did with a dial indicator and rod through the pre chamber. Cat lists the piston travel for the correct engine crankshaft location. And turn the pump drive gear till fuel just starts to drip from line; bolt up and recheck. Just make sure no1 is on its compression stroke, not exhaust !
plate makes it a lot easier tho !
 

tctractors

Senior Member
Joined
Oct 9, 2007
Messages
2,412
Location
Worc U.K.
Hi Merv, my plasic degree disc is always in my truck and easy to use on anything that rotates? rather than use use the Cummins Style dip measurment on piston height I would find my lock plate and use that, the times that I have spill set 300 series engines usualy involves someone that has done something to the pump, then I get called in because things fail to start, on the D342 motors they can get into a pickle in the gear chest after big hours, this is the best way to convince the owners that its due a Birthday.
tctractors
 

Bryant_955L

Well-Known Member
Joined
Apr 19, 2014
Messages
76
Location
Wasatch
You guys are great. The Cat is purring like it should. It is amazing to me just how crappy the engine runs with the timing off. I had all kinds of black smoke and the motor would only run at higher RPM's. I literally was thinking I would have to tear the motor down completely and start over. But with the help of this forum I was able to put my worries behind me. When I used the tool and timed the pump correctly this time I couldn't believe the difference on how the motor ran. There is no black smoke and the motor runs very smooth. I noticed in the manual that I need to run the motor at 1600 RPM for the first 4 hours to break it in. What does this Forum suggest for a break-in on the motor?
 

Mark Moyle

New Member
Joined
Jun 5, 2018
Messages
2
Location
Platinum, Alaska
I’m also having issues with a 3304 75kW genset. I’ve rebuilt the engine three times now...has over 94k hours. The last overhaul included a new crankshaft in addition to cylinder kits. Punched in new guides, ground the valves and seats...32k hours on the cylinder head before rebuild. Changed out the seals and felts on the injection pump and replaced a few parts in the Woodward governor. First start couldn’t get the engine rpm to run above a few hundred RPM....and it needed starting fluid to start? Thought I may have made a mistake on the gear timing, pulled the front cover. Was correct, reinstalled the cover with another new crank shaft seal. No joy...still didn’t run correctly. I sent the assembly to NC Machinery in Anchorage and asked...tell me what I did wrong. Turned out the gasket between the governor and center section on the pump was the wrong one...didn’t have the oil supply hole for the governor. Reinstalled the pump..ran like poo wouldn’t carry a load and made oil. Turns out the pump guy at NC hadn’t pulled the barrels and plungers, and I may have got one of the plungers out of time on the rack?..sent the assembly back to Anchorage to Advanced diesel.. reinstalled... nice warm building still needed starting fluid to start. Rattles like hell, I believe the timing is to fast. The pipe plug for the 3/8” bolt into the flywheel is just inboard and below the turbo drain line. Insured I was on the compression stroke. Pulled the plug on the side of the injection pump and inserted a number 30 drill bit. Tightened the bolt on the pump gear...so...what am I doing wrong...is it sometimers on my part and I’m timing the pump wrong?
 

Mark Moyle

New Member
Joined
Jun 5, 2018
Messages
2
Location
Platinum, Alaska
A person holding his thumb on number one injector hole while I rotated the crank. Installed the 3/8” bolt in the flywheel. I haven’t used an dial indicator yet to find TDC on number one piston. If I remember correctly the flywheel bolts on one way.
 

d9gdon

Senior Member
Joined
Feb 12, 2010
Messages
1,517
Location
central texas
Check the bushing on the injection pump idler gear in your front gear train. They are famous for wearing out, and yours has had plenty of hours to wear out.

Also, are you rotating the engine at least 60 degrees in the direction of rotation when you are pin timing the injection pump? You have to do that in order to take the gear train slack out of the timing. Don't back up if you miss it, go on around again to pin time it correctly.
 
Last edited:
Top