Compression/Ring Test (1 Viewer)

[LCnAZ]

Hi guys. We did a compression test today and also tested for change with a little oil in each cylinder looking for a difference before and after the oil. All had tiny or no change. Good news.

Low cylinder was 130, two were at 135, two at 140, and one at 145. This is pretty good for a 240K all original 3FE isn't it? This was actually a bit improved over the last test. Since then valves were adjusted and changed oil to 10W-40.

 

[OSS]

Those compression results are very good for that engine.

 

[LCnAZ]

Those compression results are very good for that engine.

Thanks for the confirmation. I guess the fact that it doesn't have the uphill pull it used to have when the cylinders were 140, 145, 150 is to be expected. "Downshift, sir."

 

[OSS]

If you're comparing power you used to have years ago compared to what you feel now, who knows, maybe the gasoline of today ain't what it used to be in the old days.
Not the engine's fault but the fuel (for one possibility).

I had lower compression numbers than you do on my 2F and when I'd take the cruiser to Mexico and run it on Premium Mexican gas (the good expensive stuff) my engine would transform into a completely different beast. It felt like I had a V8 and I had so much more torque when flooring it up mountain grades.
The engine never performed like that in the states running any grade of USA gas - so the quality of the fuel does make a difference in power.

In the "old days" in Mexico before they had premium fuel, the only gasoline available was the stuff they call Magna Sin which feels like octane 85 gasoline. My engine ran like crap on that stuff, pinging and loss of power, so back then I used to bring an octane booster additive to make the fuel usable.

 

[LCnAZ]

If you're comparing power you used to have years ago compared to what you feel now, who knows, maybe the gasoline of today ain't what it used to be in the old days.
Not the engine's fault but the fuel (for one possibility).

I had lower compression numbers than you do on my 2F and when I'd take the cruiser to Mexico and run it on Premium Mexican gas (the good expensive stuff) my engine would transform into a completely different beast. It felt like I had a V8 and I had so much more torque when flooring it up mountain grades.
The engine never performed like that in the states running any grade of USA gas - so the quality of the fuel does make a difference in power.

Interesting point. I do now only use 91 octane from a reliable source. Around here that's Chevron, Shell, or Speedway. FWIW, the fuel filter is also quite new, and soon to replace all the vacuum lines.

For a while I tried Costco fuel with our late model Sequoia. Sucked!

 

[kirvesmies]

cornholieo infused fuel does not have the same btu's as fuel without it. so look for ethanol free stuff. you should notice a marked difference in fuel consumption for the better
n nothing wrong with those numbers by the way

 

[LCnAZ]

cornholieo infused fuel does not have the same btu's as fuel without it. so look for ethanol free stuff. you should notice a marked difference in fuel consumption for the better
n nothing wrong with those numbers by the way

Thanks for that info. I did some quick research on gasoline in my area. It is conventional/no-ethanol April through September, then we get stuck with an ethanol blend for the winter. It all comes from two pipelines; one from CA, one from El Paso. The additives are done at the local depots. I do notice that gasoline smells different than it did when I was a kid in the 50s and 60s.

 

[LCnAZ]

Not the engine's fault but the fuel (for one possibility).

Given I'm using the 91 octane fuel as specified, the compression numbers are "good," and leak back also okay, what else might I look for? I have never found any leaking vacuum lines. Fuel filter is new. Stretched kickdown cable adjust to specs (made huge difference). Did a super-duper fuel, induction, injector cleaning process (Justice Brothers). Just brainstorming a bit.

 

[OSS]

While the engine may have lost some umph due to increasing years, the point I made previously is that the gasoline available today doesn't have the same energy density as the stuff available 20 year ago. Octane doesn't equate to energy density, only to how slow it will burn. Alcohol "enriched" gasoline which we all have to burn now can have a very high octane rating (to prevent pinging) but not have the equivalent energy as old time pure gasoline.

The quality of the fuel you're using may not be the reason why the engine is less peppy than you remember, but I just thought I'd throw that variable into the equation.

Are you sure that the auto transmission isn't a suspect?

 

[cruisermatt]

There's no way you can tell 10psi of cylinder compression difference from the drivers seat. That's placebo. I have a 40 in with 70psi across all six and runs amazing for a regular 2F.

Also valve lash shouldn't make a difference on a compression test FYI

 

[Cruzerman]

I'm using the 91 octane fuel as specified

Where is that specified?

 

[LCnAZ]

Where is that specified?

Page 148 of the OM describes "Research Octane Number 91 (Octane Rating 87) or higher." I ran 87 up until about 500 miles ago (about 30 years)...when somebody here on the site sounded off that 91 is what the engine is designed for. A little research on line to respond to your question has revealed that the U.S. equivalent of RON is our lower octane number. It is the same fuel, just a different test here. Sounds like EPA meddling to me. So RON 91 is 87 Octane in the U.S.. Back to 87...unless I can feel a difference.

 

[LCnAZ]

While the engine may have lost some umph due to increasing years, the point I made previously is that the gasoline available today doesn't have the same energy density as the stuff available 20 year ago. Octane doesn't equate to energy density, only to how slow it will burn. Alcohol "enriched" gasoline which we all have to burn now can have a very high octane rating (to prevent pinging) but not have the equivalent energy as old time pure gasoline.

The quality of the fuel you're using may not be the reason why the engine is less peppy than you remember, but I just thought I'd throw that variable into the equation.

Are you sure that the auto transmission isn't a suspect?

Interesting...and disappointing.

I don't suspect the transmission for a couple of reasons. It started to fail/slip at 205K, and was rebuilt then. My point is that I have a reference for how "normal" and "abnormal" feel, and I don't feel anything other than normal transmission (unlike when it was slipping or the kickdown cable was slack). Given the transmission rebuild only has 35K on it, I would think it still has a good bit of life in it.

Here's another factor I didn't mention originally. With the restoration, I added weight. I went from stock tires to 31x10.5 and the ARB front bumper.

Another factor may be relative. My daily driver is a late model Sequoia which, of course, is a rocket by comparison. I'm pretty much able to resist too much association with that since I'm the original owner of the 62 and know how it's felt over its life.

 

[OSS]

I think that might be what you're feeling: bigger tires and more weight.

 

[LCnAZ]

I think that might be what you're feeling: bigger tires and more weight.

I suspect you're right. If I add the wifey and the lab, it works noticeably harder on hills. Given that I have the transmission operating temperature under control now, I suppose I'll just manually downshift more.