T.R | Title | User | Personal Name | Date | Lines |
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80.1 | | HSOMAI::FISHER | | Wed Jan 08 1992 12:54 | 14 |
|
I have never, ever heard of letting the engine simply idle away.
For one, getting a fresh engine to idle at all is often difficult
if not impossible. At higher speeds you should build more cylinder
pressure, forcing the compression rings against the cylinder wall and
helping to promote 'break-in' Also, if you are using a high volume
(as opposed to high pressure) oil pump, simply letting the engine idle
may produce lower oil pressures than running at a slightly elevated RPM
Keep in mind also, that 2000 rpm *HARDLY* constitutes revving the
engine, so I wouldn't worry to much about following what is the
generally accepted method of engine break in. I would strongly advise
you Dave to solicit other opinions than those given by your 'mentor'
Tom
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80.2 | DO NOT idle during cam break -in | TINCUP::MFORBES | But, this one goes to 11... | Wed Jan 08 1992 14:16 | 27 |
| Dave,
I have never ever heard of breaking in the cam by idleing the engine. I have
ALWAYS heard that idling will destroy the cam/lifters. In fact, I have always
thought that you NEVER let a new engine idle until the cam/lifters have been
broken in. You should run it at 2500-3000 rpm (vary it between the two) for
about 20 minutes not 3-5 as you said. Maybe you have something wierd with
your cam that it only needs 3-5 minutes. I have never heard of that short of
a time.
While you are breaking in the cam, if you need to shut it down before the 20
minutes is up (leaks, coolant temp), shit it right off. Do not idle it! If you
have shut it off, when you restart it, bring it right back up to speed with no
idle time.
What I did with mine is to set the idle screw on the carb sh taht it sould not
drop the idle below about 2300 rpm. It worked good and I could adjust the idle
screw up or down while breaking in the cam.
When are you going to do it? I will be out of town this coming weekend and next
week. If you are doing it before then or after, let me know and I'll take a ride
to Denver and lend a hand if you'd like.
Let me know,
Mark
dtn 592-4108
home 719-592-4108
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80.3 | OK... So I did it... | CUJO::BROWN | Dave Brown | Wed Jan 08 1992 19:37 | 19 |
|
Re: -1
You are sure welcome to come over and lend a hand but I just did the
breakin. I varied the RPM between 2200 and 2800 RPM for about 20
minutes. I sure it all works out OK! The engine runs quite smoothly in
this RPM range and maintains about 60 PSI on the oil. I am sure glad
that I bought the mondo radiator that I did because the temp leveled
out at about 185. Also I tried briefly to see how my 3000 RPM chip
works (I have it in there only initially) and sure enough it started
cutting out at 3000 RPM and filled my garage with killer hi-octane
fumes. Then I stopped it and looked for drips underneath - not a one!
What a deal!
What's next. Take it for an easy drive? Will have to wait a while
for that seeing as how the snow situation is a bit intense.
Dave
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80.4 | Take 'er for a drive and start the breakin | TINCUP::MFORBES | But, this one goes to 11... | Wed Jan 08 1992 19:59 | 13 |
| Yes, the next step is to take it for a ride. Did you change the oil
and filter after the 20 minute cam breakin? You are supposed to. The
molly lube used to assemble the engine can plug the oil filter
sometimes. I was told to chenge the oil and filter again after 500
miles. After that it's normal filter and oil change intervals.
Congratulations! Fun isn't it?
I'll try to make it up there soon. I need to go junk yarding up there
and look for some Vega parts.
Mark
Mark
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80.5 | Vary your speed and engine brake.. | LJOHUB::BEAUDET | Tom Beaudet | Thu Jan 09 1992 08:27 | 10 |
| After cam breakin I take it for a drive and vary my speed from about 35
to 55 MPH for about 30 minutes. (or what ever speed will get you
1800-2200 RPM in high gear)
Drive at 35 and slowly accelerate to 55 hold it there for a few minutes
then let off the gas and let it "engine brake" down to 35.
Supposedly this helps the rings to seat as well...works for me.
/tb/
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80.6 | Why 2500 RPM? | NWTIMA::ELLISONRA | | Thu Jan 09 1992 10:23 | 7 |
| Dave,
The reason for 2000-2500 rpm breakin is to assure lifter rotation.
Flat tappets have a crown on them when new to help them rotate.
If they don't start rotating on breakin? Bye Bye cam lobe! Common
with high valve spring retes.
Randy
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80.7 | | CUJO::BROWN | Dave Brown | Thu Jan 09 1992 12:44 | 15 |
|
Randy,
One thing I noticed about my cam/lifter setup is that in relation
to the lifters, the cam lobes ride on the very rear edge of them. This
I suppose is to force them to spin too.
Re: Oil change?
I was wondering if I ought to do that now. OK, I will but I'll have
to warm the engine up again before I do it. Now all I need is for the
snow to go away so I can go for a drive...
Dave
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80.8 | | NWTIMA::ELLISONRA | | Thu Jan 09 1992 14:05 | 13 |
| Yeah Dave.Thats right!
In regard to oil changes, eveybody has their own preferences.
I like to change it after the breakin, then after 50 miles" most
of which I accel and decel a lot in gear. The decel helps draw
oil through tight valve guides and bottom edges of the comp rings.
Then 250, 500, 1000 oil changes Dave.
Gotta go!
re
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80.9 | | BARUBA::REARWIN | the quality of mercy is not strained | Fri Jan 10 1992 07:36 | 4 |
| In addition to the 30 minutes at 2000+ rpm, I've been told to use GM
Engine Oil Supplement, 1 pint, added to the oil, initially. Then after
that time, change the oil and filter.
Matt
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80.10 | for the one who want to know..... | CSC32::J_KALINOWSKI | Forget NAM?....NEVER! | Fri Jan 10 1992 08:26 | 12 |
|
For general information....
The bottoms of flat tappets are usually ground on a 32" radius.
Also the centerline of a cam lobe never ends up dead centre in the
lifter bore. It is always offset forward or rearward in the block in
relation to the lifter bore. Watch those pushrods spin while the engine
is running with the valve covers off! Roller lifters are another
matter. You can even swap a cam and use the old lifters.
-john
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80.11 | Gotta keep those new lobes lubed | HSOMAI::HARDMAN | Talk softly, carry a big gun... | Wed Jan 22 1992 23:37 | 9 |
| According to the instructions that came with my RHS engine, the idea
behind varying the rpm and keeping it high is to make certain that the
cam lobes all get lubricated. The cam bearings are pressure fed but the
cam lobes are splash fed. Keeping the revs up keeps lots of oil flying
around in there. Varying the rpm changes the splash to make sure that
everything gets wet.
Harry
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80.12 | First oil change | SSDEVO::SHUEY | | Thu Jan 23 1992 21:40 | 8 |
|
The instructions that came with a camshaft I recently installed
recommended changing the oil and filter immediately after the 20 minute
break-in period. The reason given was to get rid of the assembly lube,
which degrades the lubricating qualities of the oil and tends to clog the
oil filter.
Tom
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80.13 | Removes metal too! | RESYNC::D_SMITH | | Fri Jan 24 1992 08:21 | 4 |
| RE:- Plus metal shavings that comes from the intial tight clearances
Dave'
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80.14 | Updates? | NWTIMA::ELLISONRA | | Fri Jan 24 1992 10:48 | 10 |
| Hi Dave,
It's been about two weeks now.... Is the snow gone?
We're all on the edge of our seats waiting to hear about
the test run.
A new musclecar is born!
(:^D) Randy
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80.15 | | TINCUP::MFORBES | Excuse me, you're standing in your pizza | Fri Jan 24 1992 11:42 | 6 |
| re .13
I hope that there are no metal shavings after the initial cam breakin. I would
think metal shavings to be a very bad sign.
Mark
|
80.16 | Leaky head on my new motor | CSLALL::BSKINNER | | Thu Jun 17 1993 09:07 | 37 |
| I just finished building a 401 nailhead motor for my 66 Skylark. I
have a Grand Sport under my Skylark skin. The only things left are
tranny lines, shortened drive shaft and minor brake work. I have put
tons of dough into this motor. I had it bored out 30 over, all new
stock parts, headers etc. I have already ran the engine for 25-30
minutes to break the cam in, changed the oil and its now got about
a hour on the engine. I installed full gauges in the car so I can see
how the engine temp and oil pressure is doing. The car needs a road
test as soon as I finish up with the driveshaft etc.. I am having a few
problems, the first is when I run the engine for 10 minutes or so
sitting in the driveway the temp gauge moves slowly from 180 to 210 or
so before I shut it down, I added the top half of the fan shroud and it
made a difference, I think this one can be fixed by intalling a full
shroud, as soon as I can find one to fit. If the car was moving it
wouldn't get a chance to get this hot.. The other problem that has me
worried is the heads. I had the heads done at the machine shop and I
didn't think twice about it at first, but now I remember that when
these heads were resurfaced they were not resurfaced flat and smooth,
but had a sort of sworl type of pattern to it, this created small
grooves which is now causing me trouble. When the engine is warmed up I
can see antifreeze bubbling slowly out of the top of the head. This
engine has a water cross over pipe and a lifter galley pan so the
intake sits up on top of the heads. I know the water is not getting
into the oil, I am always checking for foaming or runny oil, so far it
looks O.K... I can see the gasket between the engine and the head, the
heads are torqued to 80 lbs, which is the max torque for these heads.
The gaskets that were used were felpro perma-torque sandwich type.. It
looks like the leak is slowing down and is external. Should I take the
heads off and have them remilled, or wait it out and watch the oil, so
far the oil pressure has remained steady at 40.. What should I do..???
I hate to remove the heads, but I don't want to lose the motor either.
Thanks,
Brian
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80.17 | | BARUBA::REARWIN | abolish the Registry | Thu Jun 17 1993 11:05 | 6 |
|
What do you mean by "the top of the head"?
Is it leaking from the interface between the head and the block, the head and
the intake manifold, or from around the cylinder head bolts themselves?
Matt
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80.18 | you may need new heads..... | CSC32::J_KALINOWSKI | Forget NAM?....NEVER! | Thu Jun 17 1993 11:41 | 8 |
|
Also find out if the heads were broached when they were rebuilt
and/or machined. Buick and Oldsmobile heads should never be broached in
that they will bend and end up having more material removed from their
ends and this is where they usually leak anti-freeze. If this is
difficult to grasp...get the info first then call me. 592-5427
-john
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80.19 | | TINCUP::MFORBES | It's NOT your father's Chevy Vega | Thu Jun 17 1993 13:42 | 9 |
| If it is leaking from the head/block mating area, try retorquing the heads. My
327 did this at first until I retorqued (with a composition head gasket). I had
no seepage at all when I switched to a steel shim head gasket.
If it is leaking from a head bolt, did you use sealer on the head bolts when
you put the heads on? You should have used some kind of sealer (i.e. Permatex
Aviation Form-a-gasket) on the head bolt threads.
Mark
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80.20 | leaker | CSLALL::BSKINNER | | Thu Jun 17 1993 13:44 | 22 |
| RE:17
This engine does not pass antifreeze thru the intake manifold, its uses
and separate water crossover pipe. The antifreeze it not leaking into
the cylinders or into the oil. You can see some leakage between the
head and the block at the top front corners of each head. This head
has a water passages in all four corners for each head only the top
front corners are leaking slightly.
Re:18
What does broached mean? If they were broached are they junk now ? I
spent 350 bucks to have them rebuilt. The felpro gaskets are much
thicker sandwich 3 piece type gaskets, the originals are usually a lot
thinner one piece steel. Can I get away with having the heads resufaced
and use the thicker type gasket ? Or should I grap a set of 425 heads
from my local junky..?
Thanks for the input, I think i'll be stopping by the machine shop for
a little talk...
Brian
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80.21 | grinder/cutter marks probably not the problem | CSLALL::NASEAM::READIO | A Smith & Wesson beats four aces, Tow trucks beat Chapman Locks | Fri Jun 18 1993 08:30 | 38 |
| Yank the heads off and replace the head gaskets. Spray copper coat on them
before you install the gaskets. I've had numerous Fel-Pro no-retorque
gaskets leak on me and have solved the problems by replacing them with
sprayed gaskets. Most of the time this occurs with heads that haven't been
re-surfaced but poor quality resurfacing will cause coolant leaks, too.
If you didn't wash the heads out before you put them on you may have gotten
a chunk of rust or scale on the gasket surface when you inverted the head
to set it on the block. This is pretty common....crap falling out of the
coolant passages when you install heads. I spray shaving cream into the
water passages before I install cylinder heads and I don't have that
problem. Once burned, twice shy. It happened to me when I did a 60,000
mile valve job and combustion chamber cc'ing on my GTX back in '69. I
thought I had the head clean but when I pulled the head back off, there was
the chunk of rust on the head gasket. New gasket, can of copper coat and a
can of shaving cream. The heads are still on the motor to this day and
don't leak. That was the first time I used shaving cream.
BTW, the grinding marks are normal. The sign of a "good" grinding job is
traces of grinding marks running in the opposite direction. i.e. the
"witness" marks from the back side of the wheel as it passes over the
already-cut head surface. This tells you that the cutter isn't tilted
slightly and cutting a convex groove across the head. When the wheel is
tilted,the head gasket will leak between cylinders because this is where the
worst of the depression exists. Seeing the witness marks tells you that the
head is perfectly flat.
The grinding marks on your head are probably not your problem (water leak).
The problem is most likely sloppy workmanship that can probably be covered
up with a bit of gasket cement (top paragraph). The head probably isn't
absolutely flat. The problem could also be that the block isn't absolutely
flat either.
...and, yes, I understood what you meant by the top of the head. Top
meaning where the head bolts to the block but under the intake manifold as
opposed to under the exhaust manifold (bottom).
|
80.22 | Head leak (cont) | CSLALL::BSKINNER | | Thu Jun 24 1993 13:37 | 13 |
| Where can I find this Copper Coat spray ? Iv'e checked ADAP, NAPA etc..
Can't find it, I'm going to try the Local Speed Shop (P.V. Speed) in
Malden, Ma... Maybe I'll get lucky. If I go to the trouble of taking
the Heads off, I think that I'll have them checked for straightness and
then Resurfaced (smooth) no ridges.. I can get the one piece (hi
compression) steel gaskets, or the thicker Felpro Perma tourque. I like
the thicker gaskets because I think that because they are thicker and
compress more that they might seal better.. which one is better ?
Thanks,
Brian
|
80.23 | | TINCUP::MFORBES | It's NOT your father's Chevy Vega | Thu Jun 24 1993 20:51 | 13 |
| I use the steel shim gaskets in my 327 and they seal fine. I had the
FelPro composition gaskets on it before and they seeped slightly until
I retorqued them.
The steel gasket will bump your compression aproximately half a point.
It you use the steel type, coat them with aluminum or silver paint
that contains aluminum powder. Spray each gasket, on both sides, with
3 thin coats of the paint and install while the paint is still tacky.
A local engine builder told me this method and it worked great. The
gaskets do not seep at all. For paint, I used Plasti-Kote High
Perfromance No. 345 silver.
Mark
|
80.24 | Permatex makes it | CSLALL::NASEAM::READIO | A Smith & Wesson beats four aces, Tow trucks beat Chapman Locks | Fri Jun 25 1993 08:14 | 18 |
|
> Where can I find this Copper Coat spray ? Iv'e checked ADAP, NAPA etc..
> Can't find it, I'm going to try the Local Speed Shop (P.V. Speed) in
> Malden, Ma... Maybe I'll get lucky. If I go to the trouble of taking
You couldn't find it in a NAPA store??????????????
You'd better change NAPA stores. I have three or four cans of NAPA/Permatex
spray Copper Coat. I got one at Merrimack Valley Auto Parts, another at
Auto Machine in Maynard and a third at the NAPA store on route 110 in
Westford. Even the NAPA store in Ayer has it.
I even remember seeing it at the ADAP store in Nashua a week and a half ago
.
Come to think of it, I think the parts store across from Cumberland Farms
in Ayer has it too.
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