Oil pressure concerns
Discussion
Hello
I am concerned about my 99 450 chim and the oil pressure.
I bought her at the end of last September so not a lot of experience, the question is am I worrying about nothing?
She’s now done 50K miles. Was serviced at 49K, had semi synthetic oil, castrol. RT racing at Sheffield
Just before Christmas I noticed a slight “rattle” when you started her up if she had been left standing for several weeks, but just thought it was down to the tappets filling up with oil?
Pulled in the drive last week and a tappet was rattling quite badly. This only happened when hot, no problems when cold.
Called Dan Malenday near Lincoln and he suggested changing the oil and putting Valvoline VR1 Racing 5W50 which I did. Filled the new oil filter with oil, turned her over and got oil pressure before starting as I have read about losing oil pump prime?
The old oil was very black considering it had only been in about 1000 miles or so?
This oil change has cured the tappet noise however,
When you start her up the oil pressure light doesn’t go out straight away like it use too? And the engine is slightly noisy until the oil pressure starts to climb on the gauge.
Oil pressure when cold nearly 45, hot ticking over 15.
When running along the road at about 2000 rpm just over 30 psi, hot engine
If you go a little quicker and start to rev at say 4000 rpm the pressure drops to between 15 /20psi, slow down and the oil pressure picks back up to 30 maybe a little over.
I’ve now done 40 miles since the oil change.
I’m proposing to get a new sender and I have facilities at work to apply pressure and see if the sender and gauge are accurate so I know what I’m seeing is correct.
Then what? As I’m sure I have a problem, people on here recommend Dan so I might let him have a look as I don’t want to carry on driving her and causing damage.
Sorry its so long but I have tried to give you all the information. Many thanks for you help and responses as I know people will help, this is a really fantastic site for help and advice.
I am concerned about my 99 450 chim and the oil pressure.
I bought her at the end of last September so not a lot of experience, the question is am I worrying about nothing?
She’s now done 50K miles. Was serviced at 49K, had semi synthetic oil, castrol. RT racing at Sheffield
Just before Christmas I noticed a slight “rattle” when you started her up if she had been left standing for several weeks, but just thought it was down to the tappets filling up with oil?
Pulled in the drive last week and a tappet was rattling quite badly. This only happened when hot, no problems when cold.
Called Dan Malenday near Lincoln and he suggested changing the oil and putting Valvoline VR1 Racing 5W50 which I did. Filled the new oil filter with oil, turned her over and got oil pressure before starting as I have read about losing oil pump prime?
The old oil was very black considering it had only been in about 1000 miles or so?
This oil change has cured the tappet noise however,
When you start her up the oil pressure light doesn’t go out straight away like it use too? And the engine is slightly noisy until the oil pressure starts to climb on the gauge.
Oil pressure when cold nearly 45, hot ticking over 15.
When running along the road at about 2000 rpm just over 30 psi, hot engine
If you go a little quicker and start to rev at say 4000 rpm the pressure drops to between 15 /20psi, slow down and the oil pressure picks back up to 30 maybe a little over.
I’ve now done 40 miles since the oil change.
I’m proposing to get a new sender and I have facilities at work to apply pressure and see if the sender and gauge are accurate so I know what I’m seeing is correct.
Then what? As I’m sure I have a problem, people on here recommend Dan so I might let him have a look as I don’t want to carry on driving her and causing damage.
Sorry its so long but I have tried to give you all the information. Many thanks for you help and responses as I know people will help, this is a really fantastic site for help and advice.
Edited by Whizz65 on Monday 14th May 20:27
Hi, have you read the recent topic, "oil pressure on 500 chim" ? Oh and there are lots of other threads on this topic, its one of my favorites...
FWIW heres my contribution ot that topic:
"" The real problem here is that there are so many variables. The pressure gauge system, i.e sender unit and gauge are notoriously inaccurate, I calibrated mine against a "wet gauge" so i could be more confident of the readings but that is a long and involved job.
The first issue is whether you have the earlier gear type pump or the later crank driven one in the serpentine front end engines, the latter having considerably more capacity and tends to maintain higher pressures especially at high temps. The type and viscosity range of the oil you are using makes a significant difference to oil pressures. Temperature obviously has a big effect too.
Consequently it is impossible to judge the actual condition of an engine in terms of component wear on the basis of the oil pressure reading alone.
As was mentioned it is more about flow than absolute pressures but as a guide my 450 serpentine at 27000 miles with calibrated oil pressure gauge filled with Mobil 1 Motorsport 15w 50 fully synthetic oil would produce an idle oil pressure of 60PSI cold dropping to just under 30 when fully hot, and 65 and 55 respectively at 3000rpm. Interestingly having just rebuilt the engine but using a different brand of fully synthetic 15w 50 I am seing 60 PSI cold but dropping to 15-20 on hot idle and 45 at 3000rpm hot. I am putting this down to the change of oil but I am suspicious that the gauge may have come out of calibration after standing for 10 months. I will need to get the wet gauge out again! end quote""
Your '99 450 will be the same as mine with the seprpentine front end. I think the 5-50 may be a bit thinner at high temps despite the 50 rating and i will probably revert to a 15-50 when i drain it, probably in a couple of weeks time, after the first 1000 miles post rebuild.
I had a very similar prob with my sender, with it suddenly dropping the indicated presure when revved over about 3.5K, it happened on a track day and gave me heart failure, it turned out to be a poor connection at the spade connector to the sender unit.
If its been standing for a few weeks you can expect some tappet noise on start up, If you get rattly tappets hot then that may be due to low oil level and brisk cornering causing oil surge and some air being picked up by the pump and finding its way into a tappet(s). As these cars develop high cornering loads and the sump isnt baffled it is particularly important to maintain good oil levels otherwise bad surge may cause oil starvation and engine damage.
Hope that helps
FWIW heres my contribution ot that topic:
"" The real problem here is that there are so many variables. The pressure gauge system, i.e sender unit and gauge are notoriously inaccurate, I calibrated mine against a "wet gauge" so i could be more confident of the readings but that is a long and involved job.
The first issue is whether you have the earlier gear type pump or the later crank driven one in the serpentine front end engines, the latter having considerably more capacity and tends to maintain higher pressures especially at high temps. The type and viscosity range of the oil you are using makes a significant difference to oil pressures. Temperature obviously has a big effect too.
Consequently it is impossible to judge the actual condition of an engine in terms of component wear on the basis of the oil pressure reading alone.
As was mentioned it is more about flow than absolute pressures but as a guide my 450 serpentine at 27000 miles with calibrated oil pressure gauge filled with Mobil 1 Motorsport 15w 50 fully synthetic oil would produce an idle oil pressure of 60PSI cold dropping to just under 30 when fully hot, and 65 and 55 respectively at 3000rpm. Interestingly having just rebuilt the engine but using a different brand of fully synthetic 15w 50 I am seing 60 PSI cold but dropping to 15-20 on hot idle and 45 at 3000rpm hot. I am putting this down to the change of oil but I am suspicious that the gauge may have come out of calibration after standing for 10 months. I will need to get the wet gauge out again! end quote""
Your '99 450 will be the same as mine with the seprpentine front end. I think the 5-50 may be a bit thinner at high temps despite the 50 rating and i will probably revert to a 15-50 when i drain it, probably in a couple of weeks time, after the first 1000 miles post rebuild.
I had a very similar prob with my sender, with it suddenly dropping the indicated presure when revved over about 3.5K, it happened on a track day and gave me heart failure, it turned out to be a poor connection at the spade connector to the sender unit.
If its been standing for a few weeks you can expect some tappet noise on start up, If you get rattly tappets hot then that may be due to low oil level and brisk cornering causing oil surge and some air being picked up by the pump and finding its way into a tappet(s). As these cars develop high cornering loads and the sump isnt baffled it is particularly important to maintain good oil levels otherwise bad surge may cause oil starvation and engine damage.
Hope that helps
Edited by tahiti450 on Monday 14th May 22:18
The problem you have is being caused by the oil pickup pipe either having a bit of silicon gasket caught in it (happened to me), or the two retaining bolts have worked loose and are allowing it to swing in the wind. Drop the sump (about an hours work) and all will be revealed.
HTH
Kim
HTH
Kim
midas dude said:
Think its the oil pressure relief spring.Cheap fix.
Same happened to me,very disconcerting.
Run it by the guys at Fernhursts,and order part.
Hope this helps,AL
This problem mainly applies to pre-serp engines with the lower capacity gear type pump, AFAIK PRV problems arent really a big issue with the crank driven pump. ON the pre serp cerainly tweaking the PRV spring or using an adjustable set up is a well recognised mod.
slikk said:
The problem you have is being caused by the oil pickup pipe either having a bit of silicon gasket caught in it (happened to me), or the two retaining bolts have worked loose and are allowing it to swing in the wind. Drop the sump (about an hours work) and all will be revealed.
HTH
Kim
HTH
Kim
The oil pick ups often have strips of waste silicone which have come away from the inside of the sump / block seal caught in them (mine certainly did when i stripped it recently) it is very unlikley that this would cause significant blockage and affect oil pressure. If the pick up is loose (never heard of this happening) then that would be a problem (equally if the gasket for it was damaged) and would result in aeration of the oil and reduced pressure (and also possibly damage to bearings).
The oil pick ups often have strips of waste silicone which have come away from the inside of the sump / block seal caught in them (mine certainly did when i stripped it recently) it is very unlikley that this would cause significant blockage and affect oil pressure. If the pick up is loose (never heard of this happening) then that would be a problem (equally if the gasket for it was damaged) and would result in aeration of the oil and reduced pressure (and also possibly damage to bearings).
[/quote]
The silicon in my pick up pipe caused exactly the symptoms described by the OP. Removing it cured the problem. I would say that was fairly conclusive proof that it did, indeed, affect the oil pressure.
Edited by slikk on Wednesday 16th May 08:30
slikk said:
The oil pick ups often have strips of waste silicone which have come away from the inside of the sump / block seal caught in them (mine certainly did when i stripped it recently) it is very unlikley that this would cause significant blockage and affect oil pressure. If the pick up is loose (never heard of this happening) then that would be a problem (equally if the gasket for it was damaged) and would result in aeration of the oil and reduced pressure (and also possibly damage to bearings).
The silicon in my pick up pipe caused exactly the symptoms described by the OP. Removing it cured the problem. I would say that was fairly conclusive proof that it did, indeed, affect the oil pressure.
Edited by slikk on Wednesday 16th May 08:30
[/quote] Ok, I stand corrected (although i did say it was, IMHO, unlikely not impossible) but I suspect that is a pretty extreme example and probably quite unusual.
Edited by tahiti450 on Wednesday 16th May 23:10
FMe, getting a bit serious... Editing each others posts. 
You cant tell for sure whats doing it, just investigate the possibilities. TBH I cant recall any tales of woe with pressure relief springs on Serp engines, could be wrong. Since the serps moved to sealant 'gasket' it does seem to be a black art getting right ~ unfortunately sounds like you have to drop the sump for the 2 most likely faults. Personally after getting that far I'd take the oil pickup off and give it a good clean (need a gasket for that). Pressure relief spring is not expensive and fairly inoubtrusive to replace (no need for costly oil change either). You are obviously checking the gauge ~ just remember if the oil light comes on its time to stop
Dave
You cant tell for sure whats doing it, just investigate the possibilities. TBH I cant recall any tales of woe with pressure relief springs on Serp engines, could be wrong. Since the serps moved to sealant 'gasket' it does seem to be a black art getting right ~ unfortunately sounds like you have to drop the sump for the 2 most likely faults. Personally after getting that far I'd take the oil pickup off and give it a good clean (need a gasket for that). Pressure relief spring is not expensive and fairly inoubtrusive to replace (no need for costly oil change either). You are obviously checking the gauge ~ just remember if the oil light comes on its time to stop
Dave
Hi
Many thanks for all the advice, very much appreciated.
I have access to a pit so I think sump off and change the oil pressure relief spring, are these standard?
Sorry not replied to you all earlier but just got back from 2 weeks in Florida, oh yes I wish I had had her over there, they are all complaining like mad as petrol is $3 a gal, (£1.50).
Thanks slikk and tahiti450 your posts are very much appreciated along with all the others.
Many thanks for all the advice, very much appreciated.
I have access to a pit so I think sump off and change the oil pressure relief spring, are these standard?
Sorry not replied to you all earlier but just got back from 2 weeks in Florida, oh yes I wish I had had her over there, they are all complaining like mad as petrol is $3 a gal, (£1.50).
Thanks slikk and tahiti450 your posts are very much appreciated along with all the others.
spend said:
FMe, getting a bit serious... Editing each others posts.
You cant tell for sure whats doing it, just investigate the possibilities. TBH I cant recall any tales of woe with pressure relief springs on Serp engines, could be wrong. Since the serps moved to sealant 'gasket' it does seem to be a black art getting right ~ unfortunately sounds like you have to drop the sump for the 2 most likely faults. Personally after getting that far I'd take the oil pickup off and give it a good clean (need a gasket for that). Pressure relief spring is not expensive and fairly inoubtrusive to replace (no need for costly oil change either). You are obviously checking the gauge ~ just remember if the oil light comes on its time to stop
Dave
Very true Spend,the thing is if you apply silicon sealer properly it should not appear in the oil strainer or anywhere else for that matter if you do its a sure sign the stuff as been applied to a dirty/oily surface(clean dry surface is critical) you only get break away with silicone with these errors in assembly over application also causes this problem,its a bit like the loctite syndrome people tend to apply way to much and this can cause more harm than goodYou cant tell for sure whats doing it, just investigate the possibilities. TBH I cant recall any tales of woe with pressure relief springs on Serp engines, could be wrong. Since the serps moved to sealant 'gasket' it does seem to be a black art getting right ~ unfortunately sounds like you have to drop the sump for the 2 most likely faults. Personally after getting that far I'd take the oil pickup off and give it a good clean (need a gasket for that). Pressure relief spring is not expensive and fairly inoubtrusive to replace (no need for costly oil change either). You are obviously checking the gauge ~ just remember if the oil light comes on its time to stop
Dave
only kidding
First I would like to thank everyone for there help.
As suggested I took the sump off last night and found the oil pick up full of silicon beads. How oil was getting through I don't know it was really packed.
All cleaned and sump well flushed out as well. Oil pressure is a rock steady 45 when cold and running and drops to about 30 at 1500 rpm, if you leave her ticking over when hot a little over 15, guessing around the 20psi mark.
My concern is the long term damage that might have been done to the engine?
I started it less than half a dozen times with the problem of oil starvation on start up, and have only done a couple of hundred miles max with this problem.
I have contacted the TVR specialist that did the last service (and re sealed the sump!) They have said take it back and they will do some checks, inc dropping the sump and inspectiong the bearing shells, what else should I get checked? Or is it best just to leave everything well alone, the old saying don't fix what's not broke.
Many thanks again for all the advice and help
As suggested I took the sump off last night and found the oil pick up full of silicon beads. How oil was getting through I don't know it was really packed.
All cleaned and sump well flushed out as well. Oil pressure is a rock steady 45 when cold and running and drops to about 30 at 1500 rpm, if you leave her ticking over when hot a little over 15, guessing around the 20psi mark.
My concern is the long term damage that might have been done to the engine?
I started it less than half a dozen times with the problem of oil starvation on start up, and have only done a couple of hundred miles max with this problem.
I have contacted the TVR specialist that did the last service (and re sealed the sump!) They have said take it back and they will do some checks, inc dropping the sump and inspectiong the bearing shells, what else should I get checked? Or is it best just to leave everything well alone, the old saying don't fix what's not broke.
Many thanks again for all the advice and help
If the oil systems been flushed,new oil replaced,pressures are right(exactly the same as mine)what do you think you are going to find out from a quick look and listen session?££££
Run it ,but keep an eye open for the obvious things till the paranoia wears off.
Glad you got it sorted anyway Paul,Al
Some times it can be as stupid at the wires to tight, tvr use zip ties on everything and if they have tied the wires to tight and not left enough slack it pulls on the connection to the sender unit when u give the engine sum stick, happened to me, felt a right fool when i took it in and they told me what it was.
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