Welcome, Guest
Username: Password: Remember me

TOPIC:

78 kz1000ltd weird back pressure in oil system? 08 Dec 2019 18:34 #815099

  • seanbarney41
  • seanbarney41's Avatar Topic Author
  • Offline
  • User
  • '79 kz1000 LTD '75 Honda CB750
  • Posts: 440
  • Thank you received: 23
Ok, engine has fresh inspection of top end with fresh valve job, head gasket, etc. Engine is MTC 1075 kit with Andrews 2x cams ported head and 29 smoothbores. Started it up about 2 months ago for the first time. Ran it for about 2 minutes on a slave gas tank just to see where I was at on this very long term project. Started great and ran good, sounded good, all good except for a couple of small leaks, one was shift shaft seal and the other was a cam end plug. Both fixed. So today, I finally got a gas tank ready and the chassis safe enough for a test ride that would tell me if it is time to start spending on expensive cosmetics. Got everything ready and fired it up. Started easily and the oil light went out quickly. Several seconds later noticed a large pool of oil growing under the bike. Shut it down and checked it out. First thought was the filter cap was leaking. It was. Checked tightness. It was loose. Tightened it, maybe half to three quarter rotation. Tried again, same result. Found the filter cap had o-ring pushed out in one spot. So I pulled the filter assembly, inspected parts, double checked the order of assembly of the bolt, spring washer and filter. It was correct. The o-ring was slightly creased and I did not have another so I flipped it over figuring on replacing it at a 100 mile oil change. Tried again...bike was sounding great. Then I noticed more puddle growing in a slightly forward location. This time an oil line to the cooler had burst...its an old Lockheart cooler, the typical period part. I figured my bad for not replacing 40 year old oil hose and set off to the parts store for new hose. Replaced hose with same id as was installed previously. Replaced hoses. Tried again. Now not at all surprised to see another large puddle growing under the filter. Filter cover was loose again and the o-ring was pushed out in the same spot. And yeah, of course I topped off the engine after every expensive puddle of wasted motor oil. Oh yeah, when the o-ring pushes out, it is accompanied by a good sqirt sideways that made it about 8 feet across the driveway.

What is going on here? I can't understand how the filter cover keeps getting loose. Is there somehow too much oil pressure? Or is it just every 40 year old part that has a chance of failing, is failing? Could this be caused by the bypass valve in the filter bolt being stuck?

Please correct my understanding of the oil flow if its wrong. ...oil goes from the pan through the filter to the main gallery to the pressure switch, here it can go either to the cam journals or through the hoses to the cooler? So if the cooler was plugged(i did flush it out with brake cleaner and compressed air), it would just go up to the cam journals as if there was no cooler installed?

I know I gotta pull the filter again to fix the o-ring, at least, but is there anything else I am missing here?

Please Log in or Create an account to join the conversation.

Last edit: by seanbarney41.

78 kz1000ltd weird back pressure in oil system? 08 Dec 2019 19:10 #815100

  • Nessism
  • Nessism's Avatar
  • Offline
  • Sustaining Member
  • Posts: 7257
  • Thank you received: 2659
Maybe the oil cooler plumbing is messed up? Pressurizing the system too much.

Please Log in or Create an account to join the conversation.

78 kz1000ltd weird back pressure in oil system? 08 Dec 2019 19:20 #815102

  • seanbarney41
  • seanbarney41's Avatar Topic Author
  • Offline
  • User
  • '79 kz1000 LTD '75 Honda CB750
  • Posts: 440
  • Thank you received: 23

Nessism wrote: Maybe the oil cooler plumbing is messed up? Pressurizing the system too much.

That's a thought...are the old Lockheart coolers directional in some way? I have been assuming that there is no specific in or out, that the oil can flow from left to right or right to left depending on the hoseing. The hose i.d. fits the fittings that had been used on the top of the oil gallery and the nipples on the cooler.

Please Log in or Create an account to join the conversation.

78 kz1000ltd weird back pressure in oil system? 08 Dec 2019 19:55 #815103

  • Street Fighter LTD
  • Street Fighter LTD's Avatar
  • Offline
  • Moderator
  • TURBO, Its Better to be Blown than Injected
  • Posts: 4797
  • Thank you received: 1953
Can we see a picture of the oil cooler fittings where they go to the engine and how it is routed

Original owner 78 1000 LTD
Mr Turbo Race Kit, MTC 1075 Turbo pistons by PitStop Performance , Falicon Ultra Lite Super Crank, APE everything. Les Holt @ PDM's Billet Goodies . Frame by Chuck Kurzawa @ Logghe Chassis . Deep sump 5qt oil pan. RIP Bill Hahn

Please Log in or Create an account to join the conversation.

78 kz1000ltd weird back pressure in oil system? 08 Dec 2019 20:17 #815105

  • loudhvx
  • loudhvx's Avatar
  • Offline
  • KZr Legend
  • Posts: 10868
  • Thank you received: 1615
Also, I assume you inspected the oil filter cover, but is there a chance it is cracked and deforming under pressure allowing the o ring to spit out?

Please Log in or Create an account to join the conversation.

78 kz1000ltd weird back pressure in oil system? 08 Dec 2019 20:20 #815106

  • seanbarney41
  • seanbarney41's Avatar Topic Author
  • Offline
  • User
  • '79 kz1000 LTD '75 Honda CB750
  • Posts: 440
  • Thank you received: 23
It is a pretty big pain in the ass for me to post pics right now due to computer hardware limitations, but I will try. It has the adapter tee that screws in where the oil pressure switch goes and the other line goes to the plug that is right there...I think. Having trouble picturing the set up right now and the bike is not at home. I have the hoses running between the carb spigots, up over the valve cover to the usual cooler location. I have the cooler in and out facing down.

But, correct me if I'm wrong, even if the cooler and/or lines were totally plugged, wouldn't the oil just continue up the oil gallery to the cam journals?

Please Log in or Create an account to join the conversation.

Last edit: by seanbarney41.

78 kz1000ltd weird back pressure in oil system? 09 Dec 2019 01:17 #815108

  • DoctoRot
  • DoctoRot's Avatar
  • Offline
  • Sustaining Member
  • Oh, the usual... I bowl, I drive around...
  • Posts: 2543
  • Thank you received: 664
Its blowing the seals out because the line is obstructed and there is nowhere for the oil to go. either your cooler is obstructed or there is an issue with you line routing. oil flow is; oilpan>pump>filter> >pressure switch>main gallery then it splits to go up to the head or to feed the crank and transmission. If you have a oil cooler plugged in at the switch junction and the pump is building enough pressure to blow the o ring out I would venture that zero oil is going into the main gallery. not good.

the only time i have heard of the filter o-ring blowing out was when a guy removed an oil cooler and just capped off the fittings on the engine rather than reconnecting, the oil had nowhere to go.
The following user(s) said Thank You: Street Fighter LTD

Please Log in or Create an account to join the conversation.

Last edit: by DoctoRot.

78 kz1000ltd weird back pressure in oil system? 09 Dec 2019 01:23 #815109

  • zed1015
  • zed1015's Avatar
  • Offline
  • User
  • Posts: 2885
  • Thank you received: 1441
Really need pics to see what you have but the oil cooler should not tee off the pressure switch as you seem to describe .
This would give alternate routes for the oil and the cooler won't work like that.
There should be two separate single take offs replacing the original one piece pressure switch .( This is basically just a link pipe in the system which contains the oil light switch )..
The slightly lowest one directly above the crankcase ,oil filter and closest to the starter motor which is the feed to the cooler from the pump and the one next to the right of it which is the return and feeds the main gallery and ALL of the engine including cams after flowing through the cooler and lines..
If any of this route is blocked then ALL the engine will be starved of oil and NO oil will reach the main gallery or cams etc.
Any blockage will cause pressure build up in the filter housing which will then deploy the pressure relief valve and dump oil back to the sump.
The leaking filter cover suggests excessive pressure in the filter housing so I would inspect the spring and ball pressure relief valve in the roof of the filter housing to see if it is jammed shut and also the oil cooler take offs and lines for restrictions.
If you want to eliminate or incriminate the cooler and lines as the cause then simply refit the one piece switch in place of the take offs to see if the issue disappears.
AIR CORRECTOR JETS FOR VM CARBS AND ETHANOL RESISTANT VITON CHOKE PLUNGER SEAL REPLACMENT FOR ALL CLASSIC AND MODERN MOTORCYCLE CARBURETTORS
kzrider.com/forum/23-for-sale/611992-air-corrector-jets-





The following user(s) said Thank You: Street Fighter LTD

Please Log in or Create an account to join the conversation.

Last edit: by zed1015.

78 kz1000ltd weird back pressure in oil system? 09 Dec 2019 02:27 #815110

  • seanbarney41
  • seanbarney41's Avatar Topic Author
  • Offline
  • User
  • '79 kz1000 LTD '75 Honda CB750
  • Posts: 440
  • Thank you received: 23
Ok guys. Thanks for responding. I got stuff to check. I still don't understand how, in stock form, these ports in question are just capped off. Also, I don't think the top end has been starved of oil, as it sounds so quiet and smooth. No clattering, bad sounds etc.

Please Log in or Create an account to join the conversation.

78 kz1000ltd weird back pressure in oil system? 09 Dec 2019 02:53 #815111

  • zed1015
  • zed1015's Avatar
  • Offline
  • User
  • Posts: 2885
  • Thank you received: 1441

seanbarney41 wrote: Ok guys. Thanks for responding. I got stuff to check. I still don't understand how, in stock form, these ports in question are just capped off. Also, I don't think the top end has been starved of oil, as it sounds so quiet and smooth. No clattering, bad sounds etc.


By capped off do you mean the m14 gallery plug near the ign cover and the other on the side of the original pressure switch ?
There are no other ports on the engine capped of as you describe where you would plumb a cooler.
If that is where the cooler is tee'd of from it won't really be doing anything useful and won't cause a restriction if a line is blocked as oil will still flow through the switch as normal.
AIR CORRECTOR JETS FOR VM CARBS AND ETHANOL RESISTANT VITON CHOKE PLUNGER SEAL REPLACMENT FOR ALL CLASSIC AND MODERN MOTORCYCLE CARBURETTORS
kzrider.com/forum/23-for-sale/611992-air-corrector-jets-





Please Log in or Create an account to join the conversation.

78 kz1000ltd weird back pressure in oil system? 09 Dec 2019 03:11 #815112

  • zed1015
  • zed1015's Avatar
  • Offline
  • User
  • Posts: 2885
  • Thank you received: 1441

seanbarney41 wrote:
Please correct my understanding of the oil flow if its wrong. ...oil goes from the pan through the filter to the main gallery to the pressure switch, here it can go either to the cam journals or through the hoses to the cooler? So if the cooler was plugged(i did flush it out with brake cleaner and compressed air), it would just go up to the cam journals as if there was no cooler installed


Just re-read this part of you original post and that Is incorrect.
STOCK oil flow is =
PAN to PUMP.
PUMP to OIL FILTER..
OIL FILTER to PRESSURE SWITCH.
PRESSURE SWITCH to MAIN GALLERY.
MAIN GALLERY to ALL ENGINE COMPONENTS.
The oil cooler fittings should replace the one piece pressure switch and simply puts the cooler inline of the flow from the pump to the main gallery .
I suspect the cooler is plumbed in parallel off the m14 test ports as mentioned in my previous post and this needs changing as it's wrong and not actually cooling the oil to any significant degree.
That aside though doesn't explain your oil leak/ pressure problems.
AIR CORRECTOR JETS FOR VM CARBS AND ETHANOL RESISTANT VITON CHOKE PLUNGER SEAL REPLACMENT FOR ALL CLASSIC AND MODERN MOTORCYCLE CARBURETTORS
kzrider.com/forum/23-for-sale/611992-air-corrector-jets-





Please Log in or Create an account to join the conversation.

Last edit: by zed1015.

78 kz1000ltd weird back pressure in oil system? 09 Dec 2019 03:35 #815114

  • zed1015
  • zed1015's Avatar
  • Offline
  • User
  • Posts: 2885
  • Thank you received: 1441
Having said all that has the PO actually converted the original one piece pressure switch to work with the cooler by plugging the oil flow at the gallery side to disable it but still keep the light switch operable and used the m14 ports to route the oil through the cooler.
That is the only way to have the cooler function correctly with the original switch housing and if any of the lines were plugged or removed then no oil at all would get to the gallery .
Beware if removing the cooler and lines that the switch housing will need to be replaced or unblocked otherwise there will be no oil supply to the engine if the above is correct.


Again ! pic's would make this easier to figure out.
AIR CORRECTOR JETS FOR VM CARBS AND ETHANOL RESISTANT VITON CHOKE PLUNGER SEAL REPLACMENT FOR ALL CLASSIC AND MODERN MOTORCYCLE CARBURETTORS
kzrider.com/forum/23-for-sale/611992-air-corrector-jets-





Please Log in or Create an account to join the conversation.

Last edit: by zed1015.
Powered by Kunena Forum