Got It Running!

[Northboundtrain]

Well, my first engine rebuild appears to be a success so far.  It started right up immediately.  I took it for the initial break in drive, and it seems to pull pretty strong.  Now I just have to have to attend to the rest of this caddy, and it may be a half-way nice vehicle some day.  

One thing I'm a little concerned about:  The oil pressure light stays on except at idle or really low rpm.  I got really nervous at first, so I backed out the oil pressure sensor while the engine was running, and oil started seaping out pretty quickly.  That eased my mind a little, but I wonder whether somethings not right.  It's an old sensor, and I ought to get a new one, but could I have okay pressure at idle, and not enough at higher rpms?

Thanks for all the help so far.

[fatmobile]

Some of those sensors are normally off and turn on when the oil pressure gets high.

[Patrick]

Screw a guage in the head to make sure, but chances are it's just the sending unit. Had a similar problem with mine. The sending unit at the filter reads up to about 2000 rpm, and the one on the head kicks in after that.There's a relay that reads rpm from the altrnator and kicks it from one to the other. I put two new sending units in mine when I did it, and the one in the head was either the wrong one or bad. Put the old one in and it works fine. Somewhere either on this board or Jack's there's a pretty good article on this thing. Try a search on "dynamic oil pressure system"

[janb]

...The oil pressure light stays on except at idle or really low rpm.  ...I backed out the oil pressure sensor while the engine was running, and oil started seaping out pretty quickly.  ..

Is this on a mechanical 1.6?  sounds like it, there should be 50PSI + at the head sensor with a new engine.  Did you check intermediate bearings?  They are the first point of Oil Pressure failure (past the pump...)   Did you pre-prime oil system before firing?

I would be very concerned with dribbles at head, while running.  I have more than once had sensors break, and they leak really bad. (I now carry a spare) As does a broken oil pressure line to a mechanical gauge.  @ 50psi, you will have a flood, even for a few seconds after shutdown.  Put a mechanical gauge at filter housing, and at head to troubleshoot.
jb

[Northboundtrain]

I bought a mechanical sensor that I will hopefully install today (if my wife lets me wrench on Easter  :? )  There are two 1/8" npt ports on the filter housing.  Should I install the sensor on the front (toward radiator) or rear (toward engine) port?

[Northboundtrain]

I put in the mechanical oil pressure sensor.  The pressure is a little on the high side I think.  Once its warmed up it idles around 10-15 psi.  When I rev it hard it can approach 75 psi.  Cruising pressure is probably 30-50 psi.  When it's cold, the pressure is higher -- 100+ psi if I rev it hard when it's cold (I'm not going to do that any more).  What do you guys think?

Also, along with the pressure sensor, I installed a temp sensor that reads in degrees F.  Cruising around town the temp stays a steady 200 deg F.  I know that if I drive up a long hill, the temp will want to climb a little higher.  What is the upper temperature limit for this engine?

Thanks for the help

[QuickTD]

That pressure sounds pretty normal. Mine is  much the same, 15-20psi at idle 50psi at 2500rpm and it pegs the 100psi guage at startup.

[Otis2]

QTD, are those the oil pressure numbers from your engine, taken after you replaced its intermediate shaft bearings?

If so, can you please post your previous oil pressure numbers from that engine (with worn I-shaft bearings), just for comparison?

[QuickTD]

Those are the numbers now, after I changed the bearings. Prior to that it got as low as 7 psi @ idle, about 20psi @ 2000rpm and 30psi @ 2500rpm cruise. The minimum spec. is 2bar (28psi) @2000rpm with 80ºC oil, yours sounds pretty normal. The cold oil pressure was always high, the relief valve opens at about 90-100psi on mine and the pressure stops rising.

[Northboundtrain]

Any thought on the upper temperature limit of the 1.6 n/a?  I noticed today that it got up to 210 deg F while driving up a hill about a mile and a half long.