Yesterday's Tractor Co.
Shop Now View Cart
   Allis Chalmers Case Farmall IH Ford 9N,2N,8N Ford
   Ferguson John Deere Massey Ferguson Minn. Moline Oliver
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   Traditional YT Forum ViewClassic View   RegisterRegister 
 ProfileProfile    Log inLog in 

Rebuilt Cat 3204 motor will not start on own power.

Post new topic    
View previous topic :: View next topic  
Author Message
New User

Joined: 07 Apr 2021
Posts: 1

Report to Moderator

PostPosted: Wed Apr 07, 2021 3:47 pm    Post subject: Rebuilt Cat 3204 motor will not start on own power. Reply to specific post Reply with quote

I hope this isn't to long of a post but I need anyone's help on this one. The motor being worked on is a PC naturally asperated 3204 cat engine. I had recently pulled the motor out of our D3 dozer due to the motor having a large oil leak between the block and flywheel housing. The motor was on the tired side so we decided to have a reputable rebuild shop rebuild our motor. It was a long block rebuild, and since we rebuilt the motor we also had the injection pump rebuilt, new and tested injectors, as well as a rebuilt lift pump. The motor went back together like a dream until we tried to start it. As of now you can start the engine with ether, shut it off and you can start it right back up again on its own. wait more than five minutes you have to use ether again.
We have a book for this motor and followed the Cat timing instructions, as well as, using the correct timing plate for the accessory drive housing. The procedure the book states was to align the timing marks on the crank and cam, pin the motor on compression number one ( both valves being closed on number one/ having vale lash at number one), installing the timing plate into the accessory drive shaft, and then torqueing the accessory drive gear while the timing plate was installed. After all this one needs to only install the pump; due to the offset cutout of the pump shaft and accessory drive shaft the pump can only go in one way. After the motor was installed and no start persisted we verified the timing marks were correct by fishing a camera light down the front of the timing gear cover. and going over the process again....and again.....and again.
After verifying timing and doing it more than just once, we then moved onto compression. We used the glow plug port and had 425 on all 4 cylinders.
Maybe 180 degrees out on valve setting i was told. We checked and even tried to set it off 180 degrees but physically couldn't due to massive lash issues, as well as, pushrod to rocker clearance issues. So valve adjustment is good.
Lift pump fuel pressure is just above 40 psi. We sabotaged our fuel line from filter housing to injection pump by removing a section of it and installing a clear hose to see if we were inducing air into the system before the injection pump. No bubbles, and we started it on ether to run it a while to make sure it had no air bubbles in a running state.
Thought the pump was possibly rebuilt wrong and sent it back to the repair shop. Said it bench tested good. I trust the pump place as we have done a lot of business with them in the past.
No air restriction for intake on motor and the starter is cranking the motor fast enough.
Only thing we haven't done is re-tested the injectors. Which number 3 and 4 when twisted apart had fuel in them but 1 and 2 did not. Don't know if that means anything or not. Injectors were torqued to 55 ft-lbs per cat spec into the pre-cup chambers and cross over lines to 35 ft-lbs per cat spec. We removed injectors to verify possibly if we had mashed one by mistake and did not.
Glow plugs are working, and pulling good amps. We even removed them and grounded them to be sure how hot they were getting. Once it starts with ether the motor runs well. Took temp readings on exhaust and looked good. We did the recommended break in period for the motor and it didn't lack power as well as any hesitation It did however smoke a light blue haze the entire time of running. Was hoping it would clear up when warm.
While trying to crank the motor we do not get smoke initially. It takes about 5 seconds for the exhaust to begin to emit smoke and 15-20 seconds to get full fuel pressure. The color is a white smoke while trying to start. The motor will not sputter or cough at all while cranking. Once started with ether and moved to 3/4 throttle and above we did notice a cylinder cutting in and out. Didn't notice that before when running it. Haven't loosened lines yet to see which cylinder it is yet. While running we get a faint blueish smoke out the stack.
I am not making oil so no diesel is leaking into the oil. We ran this motor for 3 hours at 75% load for break in.
Put 2 new fuel filters on it, cleaned the metal screen on the fitting going into the lift pump. replaced all lines from tank to injection pump which that wasn't cheep.
This is as far as my knowledge goes. I've probably left a few things out but I think its mostly there. I have been doing this a little over 10 years now and haven't really come across something like this before. Seems like the motor just isn't getting fuel. Any ideas would be much appreciated and helpful. I thank you for your time if you have read this and look forward in fixing this motor with your help.
Back to top
View user's profile
Old Magnet

Joined: 05 Mar 2009
Posts: 458

Report to Moderator

PostPosted: Wed Apr 07, 2021 9:26 pm    Post subject: Re: Rebuilt Cat 3204 motor will not start on own power. Reply to specific post Reply with quote

What do you get for fuel pressure when cranking the engine?
Those early 3204's had a built in orifice in the fuel return circuit. If that got omitted or changed cranking pressure suffers.
Back to top
View user's profile
New User

Joined: 08 Aug 2018
Posts: 9

Report to Moderator

PostPosted: Wed Apr 07, 2021 9:34 pm    Post subject: Re: Rebuilt Cat 3204 motor will not start on own power. Reply to specific post Reply with quote

Tell me more about the Long Block Rebuild. Could the rebuilder have installed DI pistons rather than PC pistons?
Back to top
View user's profile

Joined: 14 Dec 2015
Posts: 421

Report to Moderator

PostPosted: Wed Apr 07, 2021 10:14 pm    Post subject: Re: Rebuilt Cat 3204 motor will not start on own power. Reply to specific post Reply with quote

Being that you have glow plugs it is the early version of the 3204. I have had several of these. I am thoroughly embarrassed on behalf of Caterpillar for designing only one compression ring (plus one double ridge oil ring) to go each piston. I hope the rebuild shop used the upgraded piston design with more compression rings. When I overhauled one of these I had a terrible time getting it started (stayed with original pistons). It would have never started the first time without ether. I would highly recommend buying new glow plugs because it really seems to help. Even if they get hot when testing they may not be as hot as new ones. Does the starter turn over fast? If not you have to address that. After one good day's work it should start OK with new glow plugs. Your challenge does not at all surprise me if the engine isn't broken in yet. I've had four machines with the exact same 3204.
Back to top
View user's profile
Tractor Expert

Joined: 20 Oct 2007
Posts: 2272
Location: UK

Report to Moderator

PostPosted: Thu Apr 08, 2021 2:19 am    Post subject: Re: Rebuilt Cat 3204 motor will not start on own power. Reply to specific post Reply with quote

If the engine is running ok after you get it started that takes the timing out of the equation, when you crank the engine over are you getting smoke out the stack, you should be, no smoke no fuel, no start, with the fuel system serviced and you seem to trust the fuel people there are two tests I would do, first I would check the injectors for blow back, loosen the fuel lines at the injectors, with the stop control in stop crank the engine over watching the injectors for any blow back, if a nozzle sticks open it will allow compression to leak back into the pump causing an air lock, if that checks out ok stop the engine without using the stop control, stall it or, the reason is to see if it will start again from cold, if it does there is an issue with the pump rack.
Good luck
Back to top
View user's profile
Post new topic    Yesterday's Tractors Forum Index -> Crawlers, Dozers, Loaders and Backhoes All times are GMT - 8 Hours
Page 1 of 1

Jump to:  

We sell tractor parts!  We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today. [ About Us ]

YT Home  |  Forums

Modern View Forum powered by phpBB © 2001, 2005 phpBB Group

All Rights Reserved. Reproduction of any part of this website, including design and content, without written permission is strictly prohibited. Trade Marks and Trade Names contained and used in this Website are those of others, and are used in this Website in a descriptive sense to refer to the products of others. Use of this Web site constitutes acceptance of our User Agreement and Privacy Policy

TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. None of these trademark holders are affiliated with Yesterday's Tractor Co., our products, or our website nor are we sponsored by them. John Deere and its logos are the registered trademarks of the John Deere Corporation. Agco, Agco Allis, White, Massey Ferguson and their logos are the registered trademarks of AGCO Corporation. Case, Case-IH, Farmall, International Harvester, New Holland and their logos are registered trademarks of CNH Global N.V.

Yesterday's Tractors - Antique Tractor Headquarters