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Good time for engine tuning principles?

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2wrench

2wrench

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Will an open engine help me to appreciate what I'll be doing
later in the way of engine tuning?

Is it easier to appreciate what's going on at the outside
because I can see, somewhat, what is going on on the inside?
 
I would say yes. The more you grok it the better. It's all about timing and the relationship of the cycles. As the piston goes up and down the valves have to open and close and the spark must fire. The mechanical timing (amount of lift and duration) for the valves is set by the lobes on the cam, the timing of the valves in relationship to the position of piston in the cylinder by the timing chain. The gears on the distributer and the cam and where the cam is at in it's cycle when the distributer is assembled to the cam, will determine when and at what cylinder the spark is delivered.
As you put this together visualize everything in motion. I would say move it and watch, but there's only some much assembly lube, so it may be better to save those revolutions for setting the valves.
 
A good "tool" to actually see how all the bits work together is "The Visible V-8" engine model. It put all the nuances of the four stroke engine into perspective for Horsemits many moons ago.

https://www.discoverthis.com/visible-v8.html
 
Nort has good advice and is right on the mark with the internal engine in it's cyclical motion.
 
DrEntropy said:
A good "tool" to actually see how all the bits work together is "The Visible V-8" engine model. It put all the nuances of the four stroke engine into perspective for Horsemits many moons ago.
Click to expand...

Built one of those when I was about 10 years old -- it was great.

Of course what I really wanted was:

https://www.discoverthis.com/visiblewoman.html

...but that wasn't going to happen.

As a result, to this day I can definitely say I understand engines better than I understand women.
 
Dennis,

I would be very grateful if you could post a few photos
of your engine with No.1 piston sitting in TDC position.
(before the head is installed.

thanks,

dale
 
2W,

Get yourself a dial indicator with a stand (possibly magnetic) and the assembly and checking of TDC will become infinitely easier and a lot more accurate.
 
Are these dial indicators readily available in the States?
How much do they cost- not counting shippinf?

thanks,

d
 
Dale,

I think that one is $89.00 at Sears. Can you get one through them down there?
 
I'm not sure about Sears.

I already have a quality dial gauge but it has no magnetic
arm attachment. I'll be buggered if I can figure out how
to use my gauge to measure my thrust washer's end float.
They worry me constantly.

Any suggestions?

d
 
Yup, readily available. Cheap Chinese indicator & base is usually on sale under $20 at Enco :
https://www.use-enco.com
https://www.use-enco.com/CGI/INSRIT?PMAKA=628-3040&PMPXNO=948573&PARTPG=INLMK32

A very handy tool, well worth the price even if you only need it once or twice, IMO. And they do ship internationally for very reasonable prices; or at least they did when a friend of mine ordered from the Netherlands and reported it was 1/3 the price of buying locally, even after paying shipping.

However, you can't accurately find TDC with just a dial indicator. The piston doesn't move for a degree or two on either side of TDC, so you really need to start by finding two points on either side and then splitting the difference. The process is outlined at
https://www.cranecams.com/?show=article&id=3
(scroll down to "How do you find TDC")
 
Tinster said:
I already have a quality dial gauge but it has no magnetic arm attachment. I'll be buggered if I can figure out how to use my gauge to measure my thrust washer's end float.
Click to expand...
Seems like it would be easier to find something else to obsess about ... like what kind of oil to use in dashpots ... but ...

How about removing a timing cover bolt at a strategic location, and replacing it with a length of threaded rod & some nuts. Add a piece of heavy flat iron with holes drilled to fit over the threaded rod, and to mount the dial indicator. For minor tweaks, you can bend the rod &or flat iron. Depending on how your indicator mounts, you may need to put a half-twist in the flat iron, or perhaps use angle iron instead. Or perhaps a small angle bracket from the hardware store.
 
Randall, thanks for the all-thread idea. It might work with
the dial attached with industrial expoxy.

I have my dashpots filled with hydraulic pump oil.
I don't worry about the dashpots.

Thrust washers eating up my Pedro-ized engine scare the
pants off me- constantly.

d
 
Tinster said:
Dennis,

I would be very grateful if you could post a few photos
of your engine with No.1 piston sitting in TDC position.
(before the head is installed.

thanks,

dale
Click to expand...

Dale: This should be easy....long as I don't get too
excited and forget, but I doubt that will happen.

I know the number one piston is the first at the front of
the engine in the line of six. That's easy enough.
 
Geo Hahn said:
DrEntropy said:
A good "tool" to actually see how all the bits work together is "The Visible V-8" engine model. It put all the nuances of the four stroke engine into perspective for Horsemits many moons ago.
Click to expand...

Built one of those when I was about 10 years old -- it was great.

Of course what I really wanted was:

https://www.discoverthis.com/visiblewoman.html

...but that wasn't going to happen.
Click to expand...

I built one as a kid, too. And that's probably why I'm here today. I DID understand it, and understood that it's not "rocket science."

My parents gave me the "Visible Man" too. While fascinating, it's not "rocket science," either -- but I didn't become a doctor as a result...
 
TR3driver said:
Yup, readily available. Cheap Chinese indicator & base is usually on sale under $20 at Enco :
https://www.use-enco.com
https://www.use-enco.com/CGI/INSRIT?PMAKA=628-3040&PMPXNO=948573&PARTPG=INLMK32

A very handy tool, well worth the price even if you only need it once or twice, IMO. And they do ship internationally for very reasonable prices; or at least they did when a friend of mine ordered from the Netherlands and reported it was 1/3 the price of buying locally, even after paying shipping.

However, you can't accurately find TDC with just a dial indicator. The piston doesn't move for a degree or two on either side of TDC, so you really need to start by finding two points on either side and then splitting the difference. The process is outlined at
https://www.cranecams.com/?show=article&id=3
(scroll down to "How do you find TDC")
Click to expand...

Randall: Thanks for the lead on where to purchase the dial indicator. I ordered
one just now. Wish I had it now, but all good things in time, I guess. Bought it
with tax and shipping for $23.15. Unbelieveable deal! Was nearly $100 and a
special order from Kragen. Saved my year's subscription fees to the Forum on
this lead alone. I am sure that Basil thanks you as well.
 
Randall: Also visited the cranecams.com web site
on finding TDC. I found it a bit confusing. It
seems to address degreeing (finding TDC?) of the cam.

My read of the Bently Manual describes a method of
finding TDC on the flywheel first utilizing the dial
indicator, measuring twice the movement to the top the
number one piston by first rotating right, measure and mark;
rotating left, measure and mark; splitting the difference
and finally placing the final TDC mark right between
the two (and is this split measurement done with a
tape measure or some other method?)

My understanding is now once this mark is found and
noted, the cam is then installed and oriented per
the manual (for sake of brevity).

So, it seems as if crancame addresses degreeing the cam
in situations other than an engine rebuild. Am I
wrong? Does degreeing the cam have to be done as
well after this first step of finding TDC is done
as described in the Bently Manual on the flywheel/backplate?
 
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