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E type oil flow chart

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J

JIM

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Does anyone have a detailed oil flow chart for the 3.8 liter engine? I am interested in how the oil flows from the sump, through the oil pump and oil filter. Is the filter in the pressure side or the suction side of the system? Does the oil flow from the outside, through the filter to the center of the filter, then to the right side oil gallery on its way to the bearings? What is changed when the oil relief valve operates?
Is there an oil flow diagram (chart) available?
Thanks for any help.
JRH
 
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by JIM:
Does anyone have a detailed oil flow chart for the 3.8 liter engine? I am interested in how the oil flows from the sump, through the oil pump and oil filter. Is the filter in the pressure side or the suction side of the system? Does the oil flow from the outside, through the filter to the center of the filter, then to the right side oil gallery on its way to the bearings? What is changed when the oil relief valve operates?
Is there an oil flow diagram (chart) available?
Thanks for any help.
JRH<hr></blockquote>

I probably can;t give you the exact routes, but generally, oil flows from the pump to the filter assy (I believe it flows from the outside of the filter element to the inside). The Pressure relief valve simply opens if the pressure gets above a certain level (40-50 lbs probably) and dumps any excess oil straight back into the sump (only the excess). From the filter, it makes its way via galleys in the block to the Main bearing journals. The crank then had journals that carry it oil to the rod bearing journals, etc. Also, there is a pipe at the rear of the engine that splits into two branches and carries filtered oil up to the cam assembly in the head.

If I find some free time I may try to draft up a diagram with more details and post it in our Tech Section. I'd have to do a bit of research to get the exact path of the journals, etc., but that shouldn't be too hard.

Cheers,
Basil
 
Thanks for the info. on oil flow Basil.
This means the pump must be able to process dirty oil(prior to being filtered). No wonder they wear out.
Another point. I thought the relief valve functioned to bypass the filter when the oil filter was clogged up, thus the engine would still get some oil, although not filtered. (??)

If we could see a diagram, that might help.
confused.gif
 
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by JIM:
Thanks for the info. on oil flow Basil.
This means the pump must be able to process dirty oil(prior to being filtered). No wonder they wear out.
Another point. I thought the relief valve functioned to bypass the filter when the oil filter was clogged up, thus the engine would still get some oil, although not filtered. (??)

If we could see a diagram, that might help.
confused.gif
<hr></blockquote>

It does that too (if the filter is clogged the pressue will increase, but it primarily bypasses oil back to the sump to maintain the oil pressure within limits (far eample at higher RPM). Yeah Basil, a diagram would be super!
Devin
 
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by JIM:
Thanks for the info. on oil flow Basil.
This means the pump must be able to process dirty oil(prior to being filtered). No wonder they wear out.
Another point. I thought the relief valve functioned to bypass the filter when the oil filter was clogged up, thus the engine would still get some oil, although not filtered. (??)

If we could see a diagram, that might help.
confused.gif
<hr></blockquote>

Jim, there are actually two "valves" in the filter assembley. One is the "Oil Pressure Relief valve" which funtions simply to route excess oil (over pressure) directly back to the sump. This keeps the pressure going to the rest of the engine within specs. The second valve is called the "Balance valve" which is located at the base of the filter assembly and functions at 10 to 15 lbs pressure. This valve funtions to ensure that, if the filter gets too clogged, some oil (albiet dirty oil) will still reach the bearings. If you look on the bottom side of your filter base, you will see three things: First, a hose fitting one the side of the housing nearest the front of the engine. This fitting has a hose that runs from the fitting to the sump. This is where the Oil Pressure Relief (OPR) valve is. If you were to remove this fitting, the OPR valve would follow (Its a spring loaded assembly).

Now, next to the ORP valve outlet hose you will also see two bolt heads. A large one and a small one. The small one is simply a drain plug to drain oil from the housing when changing the oil. The larger bolt head is the "Balance Valve" which only functions in the event of a clogged filter so that some oil will still reach the bearings. I am fairly sure the OPR valve is on the intake side of the filter, but I'm going to check on this and verify. I'm going to try to come up with some sort of oil flow diagram for the Tech Section, but can't promise when I'll get it completed.

Basil
 
Thanks for the additional info on oil flow.
Does this mean there is no pressure relief valve in the oil pump housing down in the pan?
Looking farward to the diagram.
cheers.gif


[ 12-12-2001: Message edited by: JIM ]</p>
 
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by JIM:
Does anyone have a detailed oil flow chart for the 3.8 liter engine? I am interested in how the oil flows from the sump, through the oil pump and oil filter. Is the filter in the pressure side or the suction side of the system? Does the oil flow from the outside, through the filter to the center of the filter, then to the right side oil gallery on its way to the bearings? What is changed when the oil relief valve operates?
Is there an oil flow diagram (chart) available?
Thanks for any help.
JRH<hr></blockquote>
 
The following is from the Haynes manual. Oil is drawn from the sump and is then passed under pressure by the pump to the filter on the right hand exterior of the crankcase and thence through drillings to the big end and main bearings; the camshaft bearings are fed via an external oil pipe. A longitudinal drilling through the connecting rod feeds the small end and the gudgeon pin with oil and a small 'hold' in each connecting rod throws a small jet of oil to the cylinder wall with each revolution... The filter head assembly incorporates a removable oil pressure relief valve and a balance valve which provides a safeguard against the possibility of the filter element becoming so choked as to prevent oil reaching the bearings. Oil which passes the oil pressure relief valve is returned to the engine sump by an external rubber hose. Hopefully this helps. Paul.
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Its really amazing the amount of work the oil pump does getting all that fluid through and around the engine. When you think of the cooling and sealing that needs to be done and the fact that you are moving 10 quarts of oil, its quit a job the pump does. There are new screw on filter elements available for the E Type but I kinda perfer the canister assembly, just something really British about it. If you ever have your sump off the engine, think about installing a steel pipe into the sump for the drain hole so as to have a steel bolt into steel threads. Koolkat in Phoenix ( '68 OTS E Type)
 
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by koolkat:
Its really amazing the amount of work the oil pump does getting all that fluid through and around the engine. When you think of the cooling and sealing that needs to be done and the fact that you are moving 10 quarts of oil, its quit a job the pump does. There are new screw on filter elements available for the E Type but I kinda perfer the canister assembly, just something really British about it. If you ever have your sump off the engine, think about installing a steel pipe into the sump for the drain hole so as to have a steel bolt into steel threads. Koolkat in Phoenix ( '68 OTS E Type)<hr></blockquote>

Is it true that the XKE holds something like 11 quarts of oil? Can't remember where I heard that, but if its true - zowie, it must cost a mint to do an oil change!
cryin.gif


JD
 
12 quarts! Is that including the quart in the filter (or does a V12 have two filters
crazyeyes.gif


JD
 
I have a cartridge filter on my V12, making it impossible to prefill the filter, but I assume that the capacity listed includes the capacity of the filter, as it was listed in the owners manual of mine. Twelve quarts brought mine right up to the fill line on the dipstick after a little cranking to get the filter full. The filter is rather large, about 4 in. in diameter and 8 in. tall. It does not cost too much if you do it yourself and use normal oil, instead of the synthetics. I was originally going to use synthetic, but it would have been about $50 for the oil plus a couple of bucks for the filter.
 
Okay, here is a query concerning my 1969 4.2l. E-type Series-II 2+2: ever since my mechanic installed a replacement oil pump, the oil pressure seems to be excessively high. When cold, or at higher RPM, the gauge is off-scale! Should there not be a pressure relief valve, to regulate such excessively high pressures, before any seals might burst? The oil pressure declines to something more reasonable when a hot engine is idling, so I assume that the gauge is working.
Thank you!
 
There must be another valve somewhere on the engine, because when I used to shut my E Type down for the winter, it leaked about a cup of oil on the garage floor. I had to treat her like a vintage airplane, and store her with a large oil pan under her.........Take care.....Mike
 
If you're still needing an answer... on my '69 S2 there is a relief valve on the bottom of the filter head - right next to the hose fitting:

Relief%20Valve_zpswrb6zfty.jpg


It is my understanding that it is non-adjustable -- can only be replaced. It is rare but not unknown that the valve can be stuck so there is a remote chance it can be serviced, else replaced.

But before doing anything, I would confirm what the gauge is showing with a known good mechanical gauge. Those senders are notoriously unreliable IMO - I finally replaced my sender/gauge with a mechanical gauge from a TR6.
 
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