David Jenkins
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| posted on 13/9/04 at 01:17 PM |
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Rob,
I think you're right - the shells look OK, apart from the one that's scored. It has to be something to do with the pickup pipe, pump or
filter (I hadn't considered that).
The fact that both the pressure switch and the gauge showed a loss of pressure simultaneously suggests that they're OK.
I did spin it over with the plugs out (it got up a fair old speed, as it's running in nicely) but couldn't raise any oil pressure - in the
past I have got 10-20psi on the starter only.
As an aside - can I re-use that bearing shell? Instinct says to change it while I'm in there, but that involves time and money!  The journal
is clean and unmarked, and the bearing surface is now spotless (I'm just "careful with money", as they say!).
Stretch,
I'm not convinced about the oil breather - I had taken it out and cleaned it when I rebuilt the engine - but it won't hurt to take it off
and check it while the engine's out!
rgds,
David
[Edited on 13/9/04 by David Jenkins]
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stretch
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| posted on 13/9/04 at 01:23 PM |
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up to you
i also didnt have any problems, will just
one morning driving to the race track
drove it to a workshop, the guy told me its breathing problem, and i thought - whatever,
Spend R250 for at a day at the workshop, i can drive for hours at 7000rpm without a problem 
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Rob Lane
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| posted on 13/9/04 at 02:02 PM |
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Breathing also depends on rocker cover and oil filler cap on a xflow.
It's a good point but if it's standard system then the filler is well vented and should breathe in place of crankcase breather. Although
not ideal.
Crankcase breather was fitted that way so that fumes could be recirculated and reburnt without smell in car cabin. Not a problem on 7
Xflows in a 7 are prone to throw oil out of crank breather and ideally should have a catch tank/breather or the dreaded oil smoke/oil spill on heavy
cornering will occur. Not a problem so much in a saloon car but once in a 7 then cornering forces increase.
As to refitting shell, well I would renew shells if I wanted car to last without any further work. If it's easy to change later then refit by
all means temporarily, but change it later as trouble is brewing there.
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David Jenkins
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| posted on 13/9/04 at 02:08 PM |
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quote:
Originally posted by Rob Lane
As to refitting shell, well I would renew shells if I wanted car to last without any further work. If it's easy to change later then refit by
all means temporarily, but change it later as trouble is brewing there.
I know you're right - it's just that I'm a tight-fisted git!
rgds,
David
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MikeRJ
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| posted on 13/9/04 at 02:24 PM |
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Is it possible the filter element has collapsed internaly? If it's on the low pressure side of the pump then it won't take much to
prevent the pump working.
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David Jenkins
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| posted on 13/9/04 at 02:34 PM |
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I may well buy a new filter when I get the bearing shells - it's a small cost compared to everything else.
David
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rusty nuts
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| posted on 13/9/04 at 07:26 PM |
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David, wasn't there a thread a few weeks ago about oil pressure problems on a cross flow?? I.I.R.C. there was an oil gallery plug missing or
loose inside the timing cover, can't remember who had the problem , may be worth a search. Rusty
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WIMMERA
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| posted on 14/9/04 at 12:50 AM |
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Hi
I'm thinking along the same lines as timf in particular pump clearances, had a similar problem with a Datsun pump that had been assembled with a
thick gasket between the pump body and the cover plate, only takes a couple of thou, and when they get hot the alloy bodies expand a bit as well
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WIMMERA
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| posted on 14/9/04 at 03:56 AM |
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Another thought, it wouldn't hurt to check bearing to shaft clearances with plastigauge, just to be sure it's within tolerance
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stephen_gusterson
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| posted on 14/9/04 at 09:25 AM |
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are you saying David that you now have no oil pressure, even when cold..... that looks like something progressively failed, rather than tolerances or
whatever....
atb
steve
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Rob Lane
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| posted on 14/9/04 at 09:41 AM |
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As I understood it, the engine now has no oil pressure at all, even when just cranking.
This suggests a failure somewhere rather than just bearing wear.
This is a rebuilt engine that only did 65 miles?
There is an oil gallery plug under the timing cover but ISTR that it led to oil leaking if it was out BUT I can't remember now.
It's some time since I messed with the Xflow engine although I know the engine intimately having cut my teeth on them, so to speak. Sometimes it
takes a while to recall things. It's an age thing.
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David Jenkins
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| posted on 14/9/04 at 09:58 AM |
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Thanks to everyone who's made suggestions! All will be taken into consideration during the rebuild - none will be ignored (including the oil
breather, honest!).
At the moment I'm waiting for some replacement big-end bearing shells to arrive before I start the rebuild. I'll check all the clearances
using plastigauge while I'm at it.
While waiting, I'm degreasing the oil pickup ready for close examination/rectification. I will also check its seal in the block, and position
in the sump. The pump looks OK, but will get a full check before refitting, and there will be a new gasket and filter.
I'll also look at the oil level in relation to the pickup pipe while I'm at it.
Have I forgotten anything?
David
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David Jenkins
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| posted on 14/9/04 at 07:25 PM |
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Now here's a funny thing...
I had a good look at the oil pump while I was fiddling around - all seems OK, apart from a certain 'grittiness' when I turn it.
The main thing that catches the attention is the state of the worm gear, which has significant wear after just 60 miles (it was a reconditioned unit
bought when I originally rebuilt the engine). the gear on the original pump is in perfect nick, even though it's probably the original unit
fitted by Ford 25 years ago. I've put the old pump back on as it's in good nick and within tolerances, and matches the worm on the cam,
which is also original (but reground).
I'm sure that this has nothing to do with my problem, as the pump shaft wouldn't have been able to 'hop over' the canshaft gear,
but it shouldn't have worn like this.
Bad materials? Who knows.
David
 
Rescued attachment dscf0006.jpg
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Rob Lane
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| posted on 15/9/04 at 07:22 AM |
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Assuming it's standard materials then it shouldn't have worn that amount. But reconditioners could use any material for the gear.
What's interesting is that it looks like lack of lubrication, given that the cam lobes and that worm gear are 'drip' fed it would
suggest that oil wasn't getting to it.
Is the cam gear, lobes etc OK with no wear showing?
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Rob Lane
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| posted on 15/9/04 at 09:47 AM |
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David, Rusty might be onto something there.
There are two gallery plugs. One is outside engine, other is in timing cover alongside cam.
It's also the plug that is at end of gallery of pressure switch ! If it was loose in timing cover all oil pressure would dissappear.
Worth removing timing cover to look. I believe it has a hex key end.
Just trying to look logically at the problem.
Rob
[Edited on 15/9/04 by Rob Lane]
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David Jenkins
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| posted on 15/9/04 at 10:25 AM |
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I peered into the block with a torch - the pump gear looks OK, and the cam lobes seem to look normal.
If that oilway plug has come loose, where would the oil go? Down to the sump, or the outside world? The reason for asking is that I don't think
that I lost any oil outside the engine.
Looks like I have another job for tonight...
David
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Rob Lane
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| posted on 15/9/04 at 11:12 AM |
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If that plug was out the oil would leak into timing cover and straight to sump.
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David Jenkins
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| posted on 15/9/04 at 01:26 PM |
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Of course it does - there's a squirt of oil that goes onto the timing chain, so it must drain back to the sump...
Silly me...
David
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Lightning
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| posted on 15/9/04 at 10:11 PM |
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Are you sure the sender is OK?
On my last kit I had F all pressure, changed to capillary gauge and low and behold pressure.
X flows go well even when knackered, I find it difficult to believe that there could be no pressure at all unless the pump is not going around or the
pick up pipe is above the oil. This would be obvious. Take the sender off and crank by hand with plugs out. Oil should wee out.
Steve
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WIMMERA
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| posted on 16/9/04 at 04:46 AM |
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David, Have you had a look inside that oil pump that felt gritty, something must have gone amiss to generate the sort of loads required to destroy
that skew gear, another old diagnostic trick is to open up the oil filter and see what it has caught, bearing in mind that whatever you find has come
through the pump, I assume you have an effective strainer on the oil pick up pipe
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David Jenkins
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| posted on 16/9/04 at 04:58 AM |
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Steve,
It's going to end up being something daft like this!
Had a good go at the engine last night -
- plastigaged some of the bearings and all were 'as new' tolerances (apart from the scored one).
- Took off the timing cover and the oil gallery plug was still screwed in tight.
- The cam surfaces are fine, and its pump drive gear totally unmarked (unlike the pump's gear - see above).
- Oil pickup pipe intact - very slight possibility of an air leak where it is pushed into the block, but it looked (and felt!) tight. I had used some
gasket sealant first time round.
- Oil pickup mesh is about 4-5mm off the base of the sump.
- I see no sign of undue wear or oil leaks.
So, I'm left with:
- Not enough oil - but it worked for 60 miles, and the level was right a while after stopping the engine.
- Both oil senders failing simultaneously (but I will check that their t-piece isn't blocked).
- Oil pump pressure valve jammed, but freed itself later, maybe when I took the pump off.
- Oil filter failure (unlikely)
- Something stopping the oil getting back down to the sump quick enough, e.g. oil breather (see earlier discussion).
I shouldn't be at all surprised if I put this all back together to find that it works just fine...
rgds,
David
(this is getting like a viking saga)
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Tblue
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| posted on 16/9/04 at 05:21 AM |
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Is the camshaft correctly fitted/bearings ok? If the camshaft is moving about it could cause a loss of pressure, and it would explain the pump rotor
drive wear.
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Rob Lane
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| posted on 16/9/04 at 07:15 AM |
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I hope both senders are in a remote T piece!
If they are in side of block the T piece will definitely fail.
Happened to me, oil everywhere. Happened to everyone I've talked too about it.
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David Jenkins
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| posted on 16/9/04 at 09:09 AM |
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Rob,
You're just trying to cheer me up! 
How did you extend the senders away from the block?
David
[Edited on 16/9/04 by David Jenkins]
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Rob Lane
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| posted on 16/9/04 at 04:34 PM |
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Sorry David.
I had just finished a hillclimb run at Olivers Mount, Scarborough and was returning downhill, just before paddock the T piece let go and I was shouted
a warning by marshals. I left an oil trail on track for about 6m before I left track, fortunately not on racing line.
It's a commmon problem and the T piece fractures under vibration of engine.
Demon Tweeks and Merlin Motorsport sell a remote 'kit' for something like £13. It has adaptors, piping and joints to take it away from
engine.
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