990a crankcase pressure

The place to discuss all matters relating to David Brown Tractors. You will need to register your user name before you can post. If you have already registered could you please make sure that your location details have been completed. Go to My Account in the Main Menu on the left, and then go into "Edit Your Information" and complete your location details. Give the Country (and State/Province if you wish) if outside the U.K. County if within the U.K. Location details helps other members if you need spares, technical advice, or the nearest practical help.

DISCLAIMER -

David Brown Tractor Club Ltd
Forum/website Disclaimer

1. This [forum/website/chat room] and the advice and opinions expressed herein is not a solution for mechanical, electrical, valuations, other problems, breakdowns or issues experienced in relation to the vehicles referenced.

2. If reliance is thought to be placed on any of the information guidance or input provided such information will be expressly confirmed as appropriate to be relied upon.

3. In the absence of any such confirmation no reliance should be suggested or inferred.

4. Members must not disclose information to 3rd parties in anticipation that reliance will be given by non-members.

5. Non-members must not purport to give advice on behalf of David Brown Tractor Club.

6. If you or someone you know is experiencing difficulties or repeated breakdowns you must seek assistance for an appropriately qualified expert who holds themselves out as such.

7. Any comments are free of charge and made or posted on an ex gratia basis. No member or non-member may advertise their professional services

Any user inactive for more than 3 months will automatically be deactivated, please contact admin@dbtc.co.uk if you would like to be reactivated.

Please be aware that your user name and entered location can be seen by all members. We only store information you have entered which is your email address and username, your IP is also stored, we have no access to private passwords.

If you do not agree with your information being stored, please do not register an account, If you wish to unsubscribe at any time please email admin@dbtc.co.uk giving your username.

Amended 27/10/18

Moderators: Segrie61, admin

User avatar
bedwards1966
Posts: 908
Joined: Sun Mar 07, 2010 10:36 pm
Location: North Yorkshire

Re: 990a crankcase pressure

Post by bedwards1966 » Sat Feb 24, 2018 6:16 pm

You can probably identify which piston has a problem by pouring diesel into each cylinder and seeing which one empties.
But for the sake of removing three additional bearing caps I would be pulling the lot to have a proper inspection.

You probably know this, but the bearing caps for the conrods (and mains for that matter) are all matched and must be put back exactly as they were, I find tippex useful for marking them (once the oil is off).

bel
Posts: 45
Joined: Sat May 06, 2017 4:06 am
Location: usa

Re: 990a crankcase pressure

Post by bel » Sat Mar 03, 2018 1:40 am

I’m pulling pistons tomorrow no need to stop now. I’m looking to overhaul it completely just hope I find that oh that’s what happened. Rather than not finding anything checking liners too has anybody ever seen a hole in one

User avatar
bedwards1966
Posts: 908
Joined: Sun Mar 07, 2010 10:36 pm
Location: North Yorkshire

Re: 990a crankcase pressure

Post by bedwards1966 » Sun Mar 04, 2018 12:54 am

Oh yes, liners get holes in them caused by cavitation and corrosion - the latter being the reason why plain water should never be used in a coolant system, and antifreeze changed every two years.

User avatar
cobbadog
Posts: 901
Joined: Tue Oct 11, 2011 6:18 am
Location: beautiful Coopernook NSW. near Taree. NSW. Australia

Re: 990a crankcase pressure

Post by cobbadog » Sun Mar 04, 2018 4:49 am

You wont regret doing the complete overhaul, it is very satisfying when it is all back together and working well again

User avatar
rid54
Posts: 220
Joined: Mon Oct 13, 2014 8:20 am
Location: Vallentuna, Sweden

Re: 990a crankcase pressure

Post by rid54 » Sun Mar 04, 2018 8:08 am

Checking the liners seems like a natural thing to do, once the engine is taken apart. However, a hole in a liner wouldn't allow gasses to create pressure in the crankcase, the pressure would go into the cooling system I think.

bel
Posts: 45
Joined: Sat May 06, 2017 4:06 am
Location: usa

Re: 990a crankcase pressure

Post by bel » Mon Mar 05, 2018 1:37 am

well gentleman,
dropped oil pan and front compartment of oil pan had bearing material in it.pulled pistons checked compression rings all good front piston one with valve mark bottom ring im guessing oil ring was gone. checked all rod bearings all intact nothing abnormal. side of 2 pistons had scuff marks on them like scratches. haven't got crank bearings out yet but look like their all there.are cam bearings babbit material also? overhaul kits ive found don't say anything about cam bearings its a AD4-47A. I will keep you posted

User avatar
cobbadog
Posts: 901
Joined: Tue Oct 11, 2011 6:18 am
Location: beautiful Coopernook NSW. near Taree. NSW. Australia

Re: 990a crankcase pressure

Post by cobbadog » Mon Mar 05, 2018 3:23 am

in the old 30c engine there appears to be no bearings in place and that the journals run in the block.

joeproctor
Posts: 1738
Joined: Fri Dec 30, 2005 3:07 pm
Location: drax, nr, selby, north yorkshire
Contact:

Re: 990a crankcase pressure

Post by joeproctor » Wed Mar 07, 2018 8:21 pm

cobbadog wrote:
Mon Mar 05, 2018 3:23 am
in the old 30c engine there appears to be no bearings in place and that the journals run in the block.
are you sure about this?

joeproctor
Posts: 1738
Joined: Fri Dec 30, 2005 3:07 pm
Location: drax, nr, selby, north yorkshire
Contact:

Re: 990a crankcase pressure

Post by joeproctor » Wed Mar 07, 2018 8:22 pm

joeproctor wrote:
Wed Mar 07, 2018 8:21 pm
cobbadog wrote:
Mon Mar 05, 2018 3:23 am
in the old 30c engine there appears to be no bearings in place and that the journals run in the block.
are you sure about this?

joeproctor
Posts: 1738
Joined: Fri Dec 30, 2005 3:07 pm
Location: drax, nr, selby, north yorkshire
Contact:

Re: 990a crankcase pressure

Post by joeproctor » Wed Mar 07, 2018 8:23 pm

ARE YOU TALKING ABOUT CRANKSHAFT OR CAMSHAFT?

bel
Posts: 45
Joined: Sat May 06, 2017 4:06 am
Location: usa

Re: 990a crankcase pressure

Post by bel » Thu Mar 08, 2018 3:05 am

Camshaft. All crank shaft bearings are intact. Haven’t pulled cam shaft out yet. Bearings are made of Babbitt material and there was quite a bit big pieces 1/2 inch or bigger in front section of oil pan just trying to figure out where it came from. I know I’ll find it but like I said overhaul kits I’ve seen hasn’t showed cam shaft bearings didn’t know if it had them

User avatar
cobbadog
Posts: 901
Joined: Tue Oct 11, 2011 6:18 am
Location: beautiful Coopernook NSW. near Taree. NSW. Australia

Re: 990a crankcase pressure

Post by cobbadog » Thu Mar 08, 2018 5:09 am

If there was bearings in the block for the camshaft I could not see any of them and there was no movement on the shaft so all good. Engine runs like a clock with no noises.

User avatar
db2d
Posts: 2262
Joined: Fri Feb 24, 2012 10:01 pm
Location: Monmouthshire

Re: 990a crankcase pressure

Post by db2d » Thu Mar 08, 2018 6:25 am

There aren’t any camshaft bearings.

bel
Posts: 45
Joined: Sat May 06, 2017 4:06 am
Location: usa

Re: 990a crankcase pressure

Post by bel » Fri Mar 09, 2018 3:13 am

that definitely explains why there not in overhaul kit. thank you. so bearing material could of only come from crank bearings or rod bearings ive overhauled lots of car and pickup engines and if I saw this much bearing material in pan it was easy to see where it came from ill keep digging

User avatar
GeoffDEAL
Posts: 526
Joined: Tue Jan 27, 2009 8:25 am
Location: New Zealand

Re: 990a crankcase pressure

Post by GeoffDEAL » Fri Mar 09, 2018 3:33 am

Hi if a valve hit a piston timing must have moved when front pulley came loose check timing gear key on crank with nothing to keep it tight when pulley came loose,key could be damaged or gear key way. Also check for bent push rods they usually bend if valves hit they are easily straightened with hand press and v blocks. Best to replace exhaust valves with new ones the heads have a habit of breaking off, replacement valves dont .

Post Reply

Who is online

Users browsing this forum: No registered users and 24 guests