Hole in My new to me block--- Sugestions?

The other day I fixed a lamp. I had to replace the socket/switch, cord, plug, harp, and shade. Cost me more than a common off-the-shelf new lamp would have. But I fixed it because it was an antique Chinese porcelain fixture that is difficult and expensive to find. The lamp

At the same time, I tossed a lamp in my office. I could have fixed it, but a new one just like it cost less than the parts to repair the old one.

Around here, 250 blocks are still fairly common (although not $20). I can find a replacement faster and cheaper than fixing that kind of hole, so I would never consider repairing a block like that. OTOH, if I lived in Resume Speed, Montana and the next nearest 250 block was 500 miles away, I would be a welding fool.

Point is, you do what makes sense. Well, maybe not. After all, why would anyone go thru the pain of putting a crossflow head on a 200 block..... :oops:
 
Not worth it dude, I have found it to be cheaper to buy a whole car (to part out) than looking for an old motor and most generally you can see/hear it run before you do all the work of a swap and find out that the junk yard motor was junk and have to swap out again
 
As a small side note, an oil filter is passive, it only filters the volume of oil that can pass through the element. After that the rest just shoots through the bypass inside the filter. Usually this happens just above idle. An engine @ 2500 rpm is bypassing most of the oil through the filter. The previous owner drove it home on 5 with an open journal on the crank, the bearings are hosed.
....JG
 
Jebus":31dwtyai said:
....An engine @ 2500 rpm is bypassing most of the oil through the filter....
Click to expand...

Yet another Old Wive's Fables that refuses to die. I would like to see the scientific evidence that led you to believe this.
Joe
 
You sound so certain. Do your homework and you will see. Actually that 2500 rpm is a bit low. There are many variables to tripping the internal oil filter bypass. Was it a new filter? Was it a large filter or small one? Was it an already dirty element with 5000 miles on it? Was there contaminates from the shucked rod clogging the element? Does it have high volume/pressure oil pump. All these variables will determine when the internal back pressure inside the filter tripps the bypass.

From: http://www.mgnoc.com/_overlay/Archives/oil_filters.htm

We see that:

The spin-on oil filter has its own bypass relief valve: an “internalâ€￾ relief valve. The filter’s internal relief valve allows oil to flow past the filter element without passing through it when the filter element’s resistance to flow is above the filter’s relief valve setting. This performs the dual function of protecting the filter element from damaging high differential pressures, as well as protecting the engine from potential oil starvation caused by a plugged filter. SAE HS-806 lists five standardized internal relief valve settings. Relief valve settings of 9-12 psi tend to predominate for automotive use. Higher bypass pressures are also available (20 psi, 29 psi, 36 psi) depending on the engine manufacturer’s design philosophy.
Click to expand...

From:http://www.fram.com/carcare/faq.php

Relief (By-Pass) Valve. In a full flow system, all of the oil passes through the filter to reach the engine. If the filter clogs, an alternative route to the engine must be provided for the oil, or the bearings and other internal parts may fail, due to oil starvation. A relief, or by-pass, valve is used to allow unfiltered oil to lubricate the engine. Unfiltered oil is far better than no oil at all. This relief (by-pass) valve is built into the engine block in some cars. Otherwise, the relief (by-pass) valve is a component of the oil filter itself. Under normal conditions, the valve remains closed. When there is sufficient contaminant in the oil filter to reach a preset level of pressure differential to oil flow (around 10-12 PSI in most passenger cars), pressure differential on the relief (by-pass) valve causes it to open. This condition can occur when the oil filter has become clogged or when the weather is cold and the oil is thick and flows slowly.
Click to expand...

And YES if you are revving your engine and you have a high volume and or high pressure oil pump that exceeds the back pressure setting on the oil filter bypass valve, then you are not filtering all of the oil from the oil pump to the engine.

The whole point of my post is to show that with a possibly metal clogged bypassing oil filter and low oil pressure from the rod journal oil hole being exposed,
the bearings are hosed.

25 years journeyman level heavy equipment mechanic
...JG
 
I'd think the volume of oil pumped to be much lower than most people think.
With a engine in good condition I'd be very surprised to see 1 gal per min at almost any rpm.
So I do not see it bypassing very much.
 
The standard SBC oil pump is about 2.5 gpm, so I would assume the 250's pump to be similar or a bit less in capacity.
 
Jebus":288g0hky said:
....
And YES if you are revving your engine and you have a high volume and or high pressure oil pump that exceeds the back pressure setting on the oil filter bypass valve, then you are not filtering all of the oil from the oil pump to the engine....JG
Click to expand...

The relief valve only opens when the pressure DIFFERENTIAL exceeds the design setting of, say, 10 psi. That means there has to be 10 psi difference from one side of the filter element to the other. In a fully warmed up engine there is WAT LESS than one psi difference at ANY speed a stock Ford six can even hope to produce.

This topic creates lots of confusion because folks don't understand the difference between their pressure gauge and DIFFERENTIAL pressure. To properly measure differential pressure it is necessary to either put a gauge on each side of the filter or (more accurately) use a special gauge that references both sides of the filter. This is the type that we use on hydraulic power units in the sawmill business; our HPU's all have filter gauges mounted on them to monitor when they need changed. These filters also have bypasses in them and function just like automotive filters except they are finer so they will actually produce more backpressure than any auto filter. Believe me, a 200 hp HPU at 1000psi sends adequate flow to severely test the system.

And yes, at operating temperature there isn't a significant difference in viscosity between hydraulic oil and motor oil. The systems are certainly larger but the principles are the same, and if you think contamination is bad in an engine try letting garbage pass through a Temposonic ® servo valve :eek:

A fellow over at www.bobistheoilguy.com rigged up some gauges on his car engine. Even with really heavy oil on cold (winter) startup he was unable to induce enough differential pressure to trip the bypass.

Joe (27+ years in sawmill maintenance)
 
I got it opened up. The only bearing that looks hosed is the one that was in the pan. The internals look rebuildable. The problem looks to be a bolt loosened an then was bent then let the whole connecting rod seperated. When the crank spun around with loos parts the block gave.

I finaly found another block. A maverick guy answed my ad and is giving it to me since he swappwed a 302 like evry one else. I am glad he saw the add before it got trashed.

I will still play this wounded block unless bort buys it. He seemed pretty interested. :LOL:
 
I think worn and repaired items that we've grown with, sometimes have a special sort of charm to them...

charvelsrvza4.jpg


They may have weaknesses we know of, but we also have the experience to work around these, and the ability to resolve problems that may arise.
 
A musical instrument has some very real differences from an automobile engine :)


And old, well used guitar will have a characteristic sound that cannot be replicated no matter WHAT you do (I am a guitar player of many years).

That's not the case of an engine ;)

Glad you found a new block bronco... now I hope you just make the right decision.
 
Drove 2 hours to pickup my New/used 250. Got there and it was a 200. :splat:
 
You must log in or register to reply here.

Similar threads

M
250 Build Plan Specs (help me check my figures)
Replies
7
Views
2K
CNC-Dude
C
Back
Top