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Prolonging the life of a tire old motor...

D

dodgestang

Active Member
No 2 ways about it....the motor in my 67 is showing all the signs of being a tired old motor no matter how pretty it looks ;). Now I have plans for a power plant for this car (as in I know I want more power...I haven't decided approach)....but I'm in the middle of the brake and rear-end upgrade (yes I am putting a new rear in it too ) so I have little interest in picking up a full blown motor and trans job in the middle of peak car enjoyment season. Ideally I want to be able to scrape by till late fall when I will do motor work for the car.

So here's my problem....oil pressure.
When car is cold idling - it has plenty of pressure
When car is cold driving - it has plenty of pressure
When car is hot idling - it has virtually none (and no, I don't have a mechanical gauge, it is the idiot cluster gauge...but it is a recent development aka this driving season/last couple weeks...it always held pressure just fine previously).
When car is hot driving - it has pressure, but it seems like every time I drive it, the warmer the day, the lower the pressure is.

Car has no obvious knocks and the power is right where its always been since I bought it so I am 'assuming' my oil is thinning out (like it does...it is 10-40) and the gaps are getting wider in the bearings because of simple age. I was thinking if I switched to a straight weight oil (like 30 weight) it would mask the problem for a few months and get me through the season before I end up spinning a bearing sitting at a stop light (I've started popping it in neutral and revving engine lightly to keep pressure up and avoid idling at all). Ohh and it is full of oil...this is not a low oil situation.

I also think going from the 2.79 rear to a 3.50 is going to probably exacerbate the problem as soon as I put it in.
 
Since you are trying to stretch it out, try some Slick 50. I added that to a Jeep I had after it lost an oil pump at 60 mph. I replaced the pump in the 235 6 cyl and had a fair amount of noise. Several suggested Slick 50 and at least 30 weight oil to do the job. It brought the pressure up to a reasonable number when hot and the engine ran perfectly quiet. I ran the Jeep another 10,000 miles before selling it and last I saw it, it was running great on the same engine.

I would not do this in a good engine....just one worn out and needing a bit of a shot in the arm for a while.
 
"AzPete" said:
Since you are trying to stretch it out, try some Slick 50. I added that to a Jeep I had after it lost an oil pump at 60 mph. I replaced the pump in the 235 6 cyl and had a fair amount of noise. Several suggested Slick 50 and at least 30 weight oil to do the job. It brought the pressure up to a reasonable number when hot and the engine ran perfectly quiet. I ran the Jeep another 10,000 miles before selling it and last I saw it, it was running great on the same engine.

I would not do this in a good engine....just one worn out and needing a bit of a shot in the arm for a while.
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You just used Slick50 or used slick50 AND 30 weight?
 
Add the slick 50 along with the 30 weight. Just replace the amount of oil with the slick 50....do not over fill. Also, I went three oil changes at 3500 miles and then added another Slick 50 just because. Ran that Jeep off road in southern Az, in the heat with no issues.
 
Before you get too excited you really need to get a mechanical oil pressure gauge hooked up. With the stock gauge there really is no way to tell where you are at. Mechanical gauges are inexpensive and easy to hook up.

If you do have an engine that is wearing down and getting to the end of its life cycle there are things you can do to put a band-aid on it for a little bit but the damage is already done and you are running on borrowed time. You can increase the oil viscosity and/or install a high volume oil pump. Going from a 10w-40 to a 30w oil is a step in the wrong direction. A 10w-40 is still a 40w oil and a straigh 30w oil is still a 30w oil. At hot temp where the vicosity and oil weight measurement are taken from the 10w-40 is going to be thicker then the straight 30w. Also, a 10w-40 is still thicker when cold then a straight 40w at hot temp. The multiweight oil just helps with flow on cold starts which is something you do not want to lose. An observation that I have had is that you can gain some psi by using conventional oil vs synthetic oil. The conventional has more resistance to flow thus more pressure at the expense of flow. While oil pressure is important flow is the ultimate necessity of an engine. Oil flow helps cool the bearings, valve springs and provide the lubrication for the important internal parts.

I ran a very worn 351w with 20w-50 conventional oil and two bottles of the STP blue bottle oil treatment which was like two little containers of oil with the viscosity of honey into the engine. Even with a high volume oil pump and that thick of viscosity oil I was lucky to get 7psi at hot idle. I was getting 4-5 psi at hot idle with the synthetic 50w. While the engine was tired it would probably still be running today. If you do have increased bearing gap dimensions due to increase internal wear then just adjust your oil viscosity to compensate for the increased internal dimensions. By installing a mechanical oil pressure gauge you will be able to tell what condition your engine is in and what viscosity oil you need for your temporary "band-aid" fix.
 
When my TR6 was suffering similar symptoms I was told to use straight 30 weight oil. it helped some, there was no Slick 50 back then...

The British car parts/repair place I was using also suggested putting in new rod bearings as you could reach 5 out of 6 from underneath without pulling the engine. I never got to that part...
 
"midpack" said:
suggested putting in new rod bearings as you could reach 5 out of 6 from underneath without pulling the engine. I never got to that part...
Click to expand...

Yeah I would never get that far either....I am hoping to be able to facilitate a weekend "jack up the old motor and lower in a new one" and then sell this old one as a core since it 1. needs a rebuild and 2. has smog heads that I would need to change anyway. I have a Ford Racing 302 Roller block sitting here that I could use for a nice little motor....or I might just buy something turn key in the 2-3k price point.
 
To prolong its life, don't do what you let me do with DT: touch the car.
 
For the many old motors I have driven, I make SOUP out of these two items and 40 or 50 wt oil.

L_Engine_Restore.jpg
hero_ot.jpg
 
"lethal289" said:
So how do you prolong the life of a tire?
Click to expand...

The same way you prolong the life of an engine....do not let me use it.
 
"Opentracker" said:
For the many old motors I have driven, I make SOUP out of these two items and 40 or 50 wt oil.

L_Engine_Restore.jpg
hero_ot.jpg
Click to expand...

+1... sounds like your cam bearings are worn... had the same problem with a 70 Torino in high school.. as Opentracker said... 50 wt oil and some STP works wonders... just be careful if it gets cold, 50 wt doesn't like much below 50 - 55 F...
 
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