Kitcat Posted April 24, 2018 Share Posted April 24, 2018 My mighty Zetec SVT has been getting consistently low oil pressures at the track. I did a recent oil change and used 20X50. I have a 2 quart Accusump system. On a cool day I was getting readings of 35-45 (spec is roughly 55-75). I have a fairly new mechanical oil pressure gauge, the Caterham supplied unit was pretty useless. When my mechanic checked oil pressure at his shop late last year my oil pressure gauge was accurate. Any thoughts on solutions? Maybe try 20W60? How hard is it to access the oil pressure relief valve spring (i.e.where is it???). Link to comment Share on other sites More sharing options...
jfgw Posted April 25, 2018 Share Posted April 25, 2018 Kitcat, Have you already tried 10W40? That's what I use in my identical engine on track - no accusump and running a Raceline baffled wet sump. Rocky Mountain apparently recommended this to the previous owner of my car if the track oil pressure got too low on 5W30. James Link to comment Share on other sites More sharing options...
Kitcat Posted April 25, 2018 Author Share Posted April 25, 2018 Never ran less than 20W50. I thought thinner oil could cause lower pressure? Link to comment Share on other sites More sharing options...
xcarguy Posted April 25, 2018 Share Posted April 25, 2018 Kitcat, A few thoughts/considerations: worn bearings (rod, main, cam). Any/all will cause a reduction in oil pressure. Clogged oil filter. Oil viscosity. It’s possible to use too high of a viscosity (oil too thick, can’t flow fast enough to create sufficient oil pressure; keep in mind here that oil pressure is produced at the bearings, not by the oil pump). Temperatures come into play on this one; thick oil + cold temp = possibly lower oil pressure. Worn/leaking pressure relief valve. Aerated oil. Foaming. Tiny bubbles. Worn oil pump. A couple of questions: What viscosity oil were you running prior to 20W50? Are you getting any valve chatter (indication of lifters not filling with oil)? Link to comment Share on other sites More sharing options...
Kitcat Posted April 25, 2018 Author Share Posted April 25, 2018 Very educational Shane, thx! No valve clatter. Not 100%, but I think I have always run 20W50. My service records are off site so I will check over the weekend. I will try 10W40 then and see if that helps. We replaced the oil filter and did an oil change just before this track day. That did help pressures a bit(they were 30-40, now 35-45). Also checked oil lines for kinks, tears, leaks. Both track days were cool (40-55 degrees, cloudy). I have read that if the oil pump is worn out, the engine likely is too.... I did have a top end rebuild 2 years ago. We will probably check the oil pressure relief valve, tho it's buried in there (remove oil pan, timing belt). How do you check for aerated oil? If by looking at the dipstick, there were no bubbles, and I checked after every run session. Link to comment Share on other sites More sharing options...
xcarguy Posted April 25, 2018 Share Posted April 25, 2018 (edited) Kitcat, Aaeration is normally associated with a higher than normal oil level; excessive overfilling, which results in the engine crank actually making contact with the oil in the pan during rotation. Think of whipping up egg whites with a mixer as an analogy. But I don’t think this is your issue since quality engine oils will contain an anti foaming additive that dissipates the bubbles. As for checking for aerated oil, check the dipstick following a drive. If you have bubbles on the dipstick, you have aerated oil. The aeration itself doesn’t change the oil properties (damage oil viscosity), but it can cause a loss of oil pressure at the bearings (where oil pressure is produced) due to air rather than oil finding its way between the bearing surface and the metal component (rod, cam, crank bearings). If aeration is an issue, the first bearings to wear/fail will most likely be the rod bearings (they take a downward pounding with every power stroke). Having said all this, I’d see what oil pressure is now (using your current viscosity oil) given the warmer temperatures that are rolling around with May vs. the colder temps of March and April. As a side note (comparing apples and oranges here, but....) I have a 5.5 qt. oil pan and run 6 qts. for track events along with a 3 qt. Accusump system. In addition, I run an after-market oil pan baffle along with a crank scraper/windage tray combo, designed to prevent/minimize/maximize: - baffle: uses a series of trapdoors to maximize available oil for the oil pump sump to pickup and distribute -windage tray: minimizes oil-to-crank contact (keeps oil in the pan/ baffle which, in turn keeps oil available for the oil pump sump) - crank scraper: removes (scrapes) excess oil from the crank allwing it to migrate back to the pan - all work together to minimize/prevent aeration/oil starvation thus maximizing available oil (theoretically, results in consistently good oil pressure) Edited April 25, 2018 by xcarguy Link to comment Share on other sites More sharing options...
Kitcat Posted April 25, 2018 Author Share Posted April 25, 2018 As a further note: pressures are perfect first 3 laps(55-70), then drop to 35-45. Link to comment Share on other sites More sharing options...
xcarguy Posted April 25, 2018 Share Posted April 25, 2018 As a further note: pressures are perfect first 3 laps(55-70), then drop to 35-45. Starting to sound more and more like bearing wear (too much bearing clearance, time for replacement). However, with that being the case, I would first change to a higher viscosity oil (using a lower viscosity oil at this point would most likely result in an even lower oil pressure after warmup) and record the pressure during startup and again with the engine up to operating temp. After that, let’s revisit this thread. Fluctuations in pressure may not be as great, but will most likely still be there. If oil pressure still isn’t adequate after using a higher viscosity oil, and I were going to then pull the pan and dig out the pressure relief valve, I would think about going ahead and replacing rod and main bearings while I was there. If you did a top end rebuild, I’m assuming you replaced cam bearings. Link to comment Share on other sites More sharing options...
xcarguy Posted April 25, 2018 Share Posted April 25, 2018 Kitcat, in rereading this thread, I have to ask; has your track oil pressures always been in the 35-45 range following warmup? If so, I’d might try using the lower viscosity 10W40 per jfgw’s suggestion and see if pressure picks up following warmup. If you did this and, pressure drops, then bearings are very suspect. Link to comment Share on other sites More sharing options...
Kitcat Posted April 25, 2018 Author Share Posted April 25, 2018 Should I also cut open the oil filter and take a look in the oil filter for metal shavings/particles? The low pressure issue has been fairly recent. Not sure when it started. It was always great, so I stopped checking it (:. And the gauge is obscured by the steering wheel so it takes some effort to see it (and not drive off the track). Link to comment Share on other sites More sharing options...
xcarguy Posted April 25, 2018 Share Posted April 25, 2018 If the issue is recent, then yes, I’d cut open the filter and check for metal. My best guess is the bearings are wearing. Link to comment Share on other sites More sharing options...
glenntwincam Posted April 25, 2018 Share Posted April 25, 2018 straying to far from recommended oil viscosity can affect the operation of VVT solenoid. in some engines it will set a fault code. Link to comment Share on other sites More sharing options...
1turbofocus Posted May 1, 2018 Share Posted May 1, 2018 straying to far from recommended oil viscosity can affect the operation of VVT solenoid. in some engines it will set a fault code. That isnt the case with any of the Focus Engines Tom Link to comment Share on other sites More sharing options...
1turbofocus Posted May 1, 2018 Share Posted May 1, 2018 The PSI Relief valve is in the oil pump on the front of the engine , I also run 20/50 Mobile Syn in all my engines street or track ,I would take a look at the filter , cut it open , I would check cam caps and make sure one isnt loose , rule of thumb is 10psi oil psi per 1000 rpm I would also confirm your oil gauge is correct Tom Link to comment Share on other sites More sharing options...
oilteq Posted May 26, 2018 Share Posted May 26, 2018 Sorry, haven't been here for a long time. You can send a sample of used oil to a lab and have it analyzed for about $15. It may help determine if worn bearings are the problem. Link to comment Share on other sites More sharing options...
Kitcat Posted May 27, 2018 Author Share Posted May 27, 2018 (edited) The assessment is ongoing. Since it is a track-only car, I have to wait to track days to see if changes have helped. Cutting open the oil filter suggested all was well. The oil looked new. Cam caps were fine. Changing the pressure gauge added 5 lbs of pressure and my mechanic is making some additional tweaks to be sure the system is air tight. I am running Schaeffer full synthetic 5/50 and I am a bit suspicious as that is a new oil for my car (mechanic loves it) and it seems to me the pressure problems started when I began using it. So I will try a new brand of oil (Mobile1 20/50 per T.Tom's suggestion) if the latest tweaks dont help. Edited May 27, 2018 by Kitcat Link to comment Share on other sites More sharing options...
Kitcat Posted May 31, 2018 Author Share Posted May 31, 2018 Update: Added a new oil pressure gauge, fixed broken check valve, cleaned out and re-pressurized the Accusump, replaced o-ring at the pick up point in the oil pan. All worth 5-10 lbs and much steadier. So not as much bouncing pressure and more in the mid 50's than low 40's. Still occasional brief drops into the 30's. Idles in mid 30's. Reads 70's first 3 laps, then 50's. Same brand of oil: 5-50 full synthetic Schaeffer. I will change oil to some other brand before next track day. Likely Mobile 1 20/50 full synthetic. Link to comment Share on other sites More sharing options...
Alfonse Posted June 1, 2018 Share Posted June 1, 2018 Mobil 1 is now a low zinc formulation, which will keep your catalytic converter from being fouled earlier. If you aren't running a cat for 100k miles, you might want to consider a higher zinc (zddp) oil. I have been using the Driven products lately, and there are several products in both their street performance and racing oils that might be good for you. http://www.drivenracingoil.com/dro/products/competition-race-engine-oils/l/1116.html Zinc is the friction additive that helps maintain film strength and reduce friction on things like camshafts and journal bearings. There are other brands as well that the EPA regulations have not impacted in the last year plus. Google ZDDP and you can find tons of information. Link to comment Share on other sites More sharing options...
xcarguy Posted June 1, 2018 Share Posted June 1, 2018 Kitcat, Glad to see you post some positive results. BTW, I’ll be doing a sleepover in your neck of the woods tomorrow night. Arriving KCVG airport around 7:00pm. Link to comment Share on other sites More sharing options...
Kitcat Posted June 1, 2018 Author Share Posted June 1, 2018 Thx Alfonse: I remember using high zinc oils in my X-Flow. Supposedly good for flat tappet engines like it had. No cat in my Zetec car so no need for low zinc there. I will add ZDDP to the list of desired ingredients for my next oil. I think it also comes in additive form. Hey Shane enjoy your nite in the Queen City. I am already committed this eve or would offer you some hospitality. Lots going on along the river, both in KY and Cincy. And the "Over-The Rhine"(OTR) section of downtown is now a mecca for folks who like great food and micro beers (Try Rhinegeist-my son is the head brewer there and it is a happening place). Avoid Cincinnati chili at all costs:). Unless you like spaghetti with a thin cinnamon flavored meat seasoning....indigestion is guaranteed. Link to comment Share on other sites More sharing options...
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