low oil pressure on downshifts?

autoxranchero

New member
Hi,

I got a '61 Ranchero last year, it has a '68 200 in it, condition unknown. I've put a HEI distributor in it, and tuned the carb, so it runs quite well. Compression test shows between 165 and 175, except for cyl. 1 which is 155. While idling and slow test drives, the oil light doesn't come on, but if I push it a little harder, the light will flicker on the upshift, and when I push the clutch in for a down shift, it will stay on until I finish the shift. Once I'm back at the shop, it will idle fine, without turning the light on. I pulled the valve cover, and there is a lot of sludge, I also get a black puff on start up, but after that the exhaust is clean. The pistons do have oil on top when I pull the plugs.

This appears to have been a junkyard swap, I'm surprised the compression numbers are as good as they are. I've been busy working on the suspension and a t5 swap, so have only driven it about 20 miles.

Any ideas before I take things apart? I do have a mechanical oil gauge that will go in next weekend.
 
The black puff of smoke at start up can be either bad valve guides, more than likely in your case deteriorated valve stem seals or else the oil is just staying up in the valve cover area. You should be able to see if the valve stem seals are bad with the valve cover off, and they can be changed on the engine if your carful. Mostly it sounds like you need to do a really good cleaning inside of the engine while you have that valve cover off (all that sludge on top of the head) also make sure all the oil return holes in the top of the head are cleaned out good so that the oil can get back down into the pan, maybe drop the pan and check if the oil pick up screen is clogged up some. If your planing on racing it you would be to wise to re build that oil pan to help keep the oil around the pickup tube screen with welding in some baffling at the front and back of pan, maybe also a widened sump or T type style pan (Road Racing type) all depends on the type of racing you plan to do. Good luck :nod: edited
 
Thanks for the reply. I've gotten some valve seals, and will be replacing those. I've read that you can clean sludge with kerosene or ATF, would you recommend that?

I'll be doing 3 or 4 autocrosses a year with it, my main weapon of choice is a 2015 Fiesta ST. Cornering is pretty transitional, so not to many long corners in one direction. Most people don't have issues with oil pressure, but it would be easy enough to weld in some baffles. I wonder if there are some examples online.

Thanks again,

Dwight
 
Don't know which area of the country you live in but when I lived in southern Calif. there was a locale company that had a great product for that. Justice Brothers engine flush I used it often over the years on slugged up engines it would clean them up in two to three oil changes. It was available in many auto parts stores in many other states. I learned about it from working with my uncle doing oil changes and maintenance on Taxi cabs. When tearing down theose very high mileage engines they were very clean inside. I have never tried the ATF or Kerosene methods though many do if you try it be carful cause if it's really slugged inside then it can also sometimes clog up the oil pump screen too, this was something the Justice Bros. flush guaranteed against happening. As far as the oil pan mods you might take some time and read this old post (see the below link) you will find out how to make the oil pan mods near the bottom but there is also lots of other good info on racing a 200 should give you insight into just what you need to do. Good luck :nod:

:shock: Why do we keep blowing motor's

viewtopic.php?f=1&t=72474&p=556846&hilit=Why+do+we+keep+blowing+motors%3F#p556846
 
I'm in Minnesota, but I actually have a local JB salesman that stops by our business. I'll ask him about the engine flush.

Thanks for the link about the oil pan mods, I read it and I've got a lot to learn. At this point my engine is stock, but I'm sure I'll be making some mods that will raise the rpms past what is safe on an unmodified engine. My other vintage autox build is a 1975 Fiat 128. Those engines run to 7000 from the factory, and with some head work go to 8000 safely, without oiling problems (at least while autocrossing, don't know about road racing).

If it's not against forum etiquette, I could post a link to my Ranchero build on my local Autocross forum. Or recreate it here.

Thanks again.
 
Those oil pan mods would work well for just about any engine that has a wet sump oil pan and in a car used for any type of spirited driving. Many other brands of engines had these kind of baffles all ready installed in the oil pans from the factory, unfortunately these small Ford sixes were designed and built just for economy so they are as basic as you can get. Most of my racing experience has been on the drag strip (one of faveriote builds was a 1964 Ranchero) along with a little fun on the street. But the forces acting on the car and the oil in the pan (Physics) are from acceleration, deceleration, and cornering right and left. The faster the car becomes the more nessisary it is to control the oil in the pan and to keep it around the oil pickup it only takes about 30 seconds or so of oil starvation (no oil pressure and sucking air) to cause engine bearing damage. The oil light switches are set to come on at around 3 to 5 psi. For street use at idle 10 psi is a safe min. and driving around town 20 to 25 psi and the on freeway at higher speeds 30 to 35 is safe, racing you need to have more so about a min of 35 to 50 psi depending on the RPM you turn it.

Sure you could put your links for the Ford Ranchero build here or also post any pictures of it as long as you fallow the the guides (see the below link on posting pictures). I am sure many would enjoy seeing it and learning about your racing build. I once rebuilt a Fiat 124 Sport Coupe for my wife to drive think it was about a 1972 but that was long ago, great little cars. That's great that you have a locale distributor of the JB products, since my move to Az I haven't found them for sale near me yet and they don't or can't sell their products on the Online Site. Good luck :nod:

Posting Pictures
viewtopic.php?f=47&t=48863
 
:unsure: autoxranchero, so did you make any progress on fixing your low oil pressure problem? :nod:
 
I worked on it today, some progress, yes, solution no.

I got some engine flush at the local O'reillys. I followed the directions, ran the engine for 5 minutes and then drained the oil. There was definitely some chunky sludge that came out. Then I pulled the pan, which was pretty clean after the treatment, as was the pickup screen. I noticed the tube for the oil pickup seemed to be angling upwards, so I measured the depth of the pan and compared it to the bottom of the pickup. It was about 3/4" above the bottom. I don't know if that is correct, but it seemed pretty high, so I bent the tube down so there is about 1/4" gap now. Since I had to remove the sway bar and cross member, it took most of the afternoon, and I only had time for a short test drive.

It's quite a bit better. At idle, and at cruising speed there is a steady 40 psi. Corners aren't a problem, nor is pushing in the clutch for down shifting. However, hard braking caused the pressure to drop almost to zero. As soon as you let up on the brakes, it pops right back up. I hooked up both a mechanical gauge and the idiot light, and they both agree.

I put in 4.5 quarts with a new filter, and it brings it right to the full mark on the stick, so that seems right, but the oil level in the pan doesn't seem very deep when you measure from the bottom of the pan to the full mark on the stick. It seems like the pump is working fine, pressure stays the same whether idling or cruising. I didn't have time to pull off the valve cover, so I don't know how much good the flush did on the top end, the instructions say you might have to repeat the treatment on old engines. In any case I can see how the baffles would help, the pickup is near the back of the deeper part of the pan, so hard braking could easily pull the oil away from the pickup. So I guess I'll be taking it apart again, hard braking is a big part of autocrossing.

Here's a link to my build, maybe if I get time I will cut and paste into a thread here.

http://forums.mnautox.com/forum/main-fo ... ross-right
 
:beer: excellent I would say you found a big part of the low oil pressure problem with the oil pick being set up so high off the bottom of the pan. It probally got bent up at sometime during its lifetime fairly comman to see oil pans with badly bent in oil sumps. Somtimes the pans get straightened out again or replaced but often the pickup tube is not. Setting at 1/4 off the bottom is real good you could go a bit lower to 3/16 or 1/8 if you wanted, as long as you kept the clean oil and the sludge out of the inside the engine. If you build a simple baffle accross the front of pan (angled down some) that will keep the oil in the sump from climbing up the front of the pan and fix low oil pressure problem on the braking, along with one at rear of the pan sump and you should be all set. It's a great looking Ranchero and with those mods your doing it should be an excellent handler too. I am a big fan of those Watts Links I think they give the best in body / chassis control I built my first one back in 1969 for use on a 41 Willys drag racer, good luck :nod: edited
 
excellent vehicle choice, eh?
Great assembly of parts - really coming together!
Good luck w/any remaining bugs!
 
Thanks guys, the info on this site has been a great help. The next step is a Watts link, I think I've found a inexpensive solution. The new Chevy Cruze has a watts link and the cross member is exactly the right length for the width of the Ranchero frame. I'l have to shorten the links some, but I'll get a watts link for under $200.
 
how bout some DOM tubing & some rod ends
for less than $100?
 
The advantage to the Cruze watts link would be that the chassis mount crossmember is already made. I could fab everything up, but I figure my time is worth something too.
 
gotcha.
enjoyin the build, bet U R 2!
 
Autoxranchero, was wondering if you ever finished up that Watts Link yet or or finished fixing those engine oiling problems. Good luck :nod:
 
Hi, I just saw this post by Bubba. I would possibly do three more things. Change the oil pump (a lot of work), add 1 extra quart or maybe try an extra pint, go with 20w 50 oil. On your old sludge issue, it was not unusual to see the pickup screens pretty caked up. We liked to carefully clean out as much sludge as we could reach to get it out of the engine, and let the oil return to the pan
 
Well its been awhile since I visited this site, autocross season started and I'm pretty busy running my 2015 Fiesta ST. So I haven't had much time to continue work on the Ranchero.

I installed a rebuilt steering box, a 39" versus the 40" that was standard in the car. This gives me a bit more room to get in and out of the car, which was also improved by a Grant steering wheel which has a 4' dish compared to the original 6.5". I found out that the shorter steering shaft doesn't work with the column mount shifter. I thought I could just cut off an inch of the column, but the shifting mechanism prevents it from pushing all the way down on the steering box. So I ended up going to the junkyard and found a floor shift column to cut off.

I got all the parts from GM for the Chevy Cruze Watts link. I'm still going to have to fab up some brackets to get the cross member below the gas tank, and am also going to have to make some clamps for the endlinks to attach to the axle. So that project is on hold for now.

I still need to put a baffle in the pan, a new pump will go in at that time, just because they're cheap.

Currently I'm working on getting seat belts installed, need to find a way to get the backing plates in behind the boxed in door post and sill.

Maybe this weekend I'll get the seat belts in, and work on mounting the '65 Mustang parking brake mechanism I got to connect with the Explorer brake cables.

Thanks for the interest and the advice.
 
"…I got all the parts from GM for the Chevy Cruze Watts link. I'm still going to have to fab up some brackets to get the cross member below the gas tank, and am also going to have to make some clamps for the endlinks to attach to the axle. So that project is on hold for now…."
not sure it would help but I see alota stuff already made up that might be used from the Rough Stuff on-line catalogue (even 4 the seatbelt).
On the other hand, you may have all the fab skills/equip and not wish to wait for delivery.

"…put a baffle in the pan…"
nothing much 4 these I6 motors (midelothian, cantor, etc). I bet you'll come up w/one easy. When U do could U share a pic w/us?
 
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