Novice needing help with 71 350 engine

I can build them but I can not evaluate them. Give me the instructions and I can do anything but without those I am dumbfounded.

1971 Buick Skylark w/1971 Buick 350/350

My 71 Skylark makes the "no oil rattle sound" when giving excelerating (hard).

This sound is really bad when the engine is cold (make sense). When cold it makes the sound at little exceleration also.

The oil level is right on and I have not needed to add any. It is also still fairly clean looking after 1,500 miles.

Oil pump? Timing is a hair off and I will adjust that this weekend (need smaller hands to get the distributor bolt) but I don't think that is the issue for this.

I do not run this car hard at all but who doesn't like to show off every once it a while.

Also when I do excelerate there is no downshift feel to the transmission. There is no issues with top speed (unknown 125+ is too much for me, right now)

There is a lot of power in the transmission just no take off power.

I hate bringing the car(s) to a mechanic and finding out I just paid a lot for a small fix plus in this economy money IS an object.

Thank you in advance for any help. I am a novice so please use simple terms and explinations :)

I can take apart and put together anything as long as I do not have to figure out why on my own.
 
help.....

Before you do anything,,, find and purchase the shop manual that applies to your car.... it will save you a ton of money , time and effort....you can buy or borrow tools from auto supply stores, and pick up knowledge on this board or v8buick.com.... then and only then should you start in on the car... proceed slowly, so things dont overwhelm you....
 
And once you get that manual, look at how to set timing.

However, if you want a guess at a diagnosis, we need more information (you did a great job - but as usual more in needed). Does it rattle at idle? what is your oil pressure cold/warm? what type of gas are you using (92, 87, alcohol)? what has been done to the motor (I assume that a 1500 mile motor is a rebuilt motor) - such as cam, head work. What induction system do you use? (holley carb, quadrajet, twin-turbo fuel-injected)? who did the motor work (a local or nationally known builder). Did you rebuild the distributor? What is the timing set at? what vacuum do you have?

You may find that going to a mechanic could save you some money (and provide a valuable learning experience) because you'll need at minimum: a vacuum gauge, timing light, a distributor wrench (no need to get your hand down on the bolt)... and it would be nice to have a distributor tester, exhaust sniffing device (whether it be o2 sensor or emission testing), and even a chassis dyno. As long as the car is mechanically sound - the tuning cost should be cheaper then buying the tools.

and finally - please don't floor the car when it's cold, it tears it up. Wait until its warm then say "here hemi, hemi hemi" :D
 
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Thank you

First let me say I love this site it and the people on it are great.
I already have the book for the car (the biggest one I have) plus I have most of the tools (a distributor wrench is the next purchase)
I bought this car 3 years ago with no information given about it. It has defiantly been modified if not restored. There is a 1' spacer plate between the 4bbl edlebrook carb and edlebrook manifold as well as this is not the original engine (vin shows it was a 6cyl) but it is a 71 350 (by the numbers).
The timing is set to specs but I think due to the fact it bogs when I shut it off and there is a little hesitation when idling I think it is off a hair. I will be checking it again this weekend.
Concerning the 1500 miles that is when I did the last oil change, I have put approx 2000 miles on it in three years. I did the oil change because I don't know when it was done before then.
The rattle
“and finally - please don't floor the car when it's cold, it tears it up.”
I do not ever run it hard while it is cold. When I said there was a rattle when cold it is just at running speed. I baby it completely until it is warmed up.
I have put in a pertronix electronic conversion kit in place of the points. Other than that I have done nothing to the car (but polish it).
I checked the oil this afternoon after driving it for 10 mins and it was down about 3/4 quart. When warm this morning and on the highway I did accelerate hard, when I did some, not a lot of black smoke came out the exhaust and the rattle was loud. So I slowed right down. When I did the oil light came on for a second then went out. This was before I rechecked the oil level to see that it was down a little.
I do not have a pressure gauge or vacuum gauge (but will soon) so I do not know those. I use 87 octane and synthetic oil (Mobil 1 15w-40)
I hope this info helps. As I said before I am not afraid of working on the car I have rebuilt Fords, Cadillac’s, and Toyotas. I have even rewired a diesel Cadillac conversion to a 8-6-4 Cadillac computer driven engine (Headlight to brake light and everything in between rewire) BUT I was always told why and I had the instructions. I have almost all of the tools or love to buy new ones. The issue is a regular backyard mechanic around here work on the fuel injected computerized cars that you plug in and diagnose then you know what is wrong. I can do what an old time mechanic can do I just would like to do it myself without paying him to do it. I love this and other forums like this because of all of the help they have
 

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Boy, tough one to diagnose from here in Seattle... but I'll give you a couple things to look at.
1) putting the Pertronix kit on the car probably didn't do anything to your timing; however, I'd still check the springs and counter weights under the rotor to make sure they aren't loose, or a spring came loose.
2) Check the bolts that attach the transmission to the torque converter - I've had 3 different cars come up with that problem and it sounds just like a rod knock.
3) when you time the car - it's possible that the harmonic balancer has spun the ring... again, makes a great sound like rod knock (this is far more prevalent on chevys)
4) get an automotive stethoscope and pinpoint where the noise is coming from. Buicks are notorious for oiling problems, and attendant bottom end issues - that you've noticed it now may make the repair the least costly.

You said the oil was low - any ideas where the oil went? if it hasn't drained out of the motor (or been burned out) you may wish to pull the valve covers off to make sure the oil drain back holes aren't plugged.

I wish you luck - in the glass-half-full theory, maybe this is motivation to upgrade 105 cubic inches :D it works for me - I'm working on mine (oil leak -rear main) and I may actually build the motor I've been talking of elsewhere to fix the oil leak problem.... makes perfect sense to me... not so much to my wife :bgrin:

an FYI - running synthetic in a used motor that has a bunch of miles on it can be problematic because it does an awesome job of cleaning the motor - and plugging the oil galleys.... food for thought
 
Thanks

I will be checking all of those in the morning.

The car has seem to lose it's oomph. It does not have it's take off ability. I was idling it a few mins ago and I held the brake and gave it gas. It smoked a little but would not spin the tires. Again I do not beat on this car but abilities are abilities and it does not seem to have it now.
This car sat all last year and I have only taken it out a few times so far this year. Once for a long drive last weekend (round trip 100 mile each way- 2 day span) I had no issues then or prior to that. I wonder if I loosened some junk in the engine and it is plugging things.
As for the synthetic the person I bought it from said that is what was in it then so I kept it that way.
 

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if it makes you feel any better - here's a brief(ish) history of mine.... it certainly isn't smooth sailing no matter how experienced you are

http://www.bangshift.com/forum/showthread.php/11037-1970-Buick-Skylark-part-II

I'd really be interested to see what's under the rotor.... when you mash your foot in the throttle the vacuum drops which tells the vacuum canister to advance the timing. If the vacuum canister has a hole in it - it won't and the car will run fine, just be sluggish. 2 things - 1, check the vacuum line for holes; and 2 - check the vacuum canister on the distributor for 2 things... first, if you can reach the rod that connects to the ring around the distributor shaft - pull the rod towards you (with a hook or something) and put your finger over the vacuum inlet.... you should feel vacuum when you let off the rod.... or use a vacuum pump to see if it leaks. the Second thing is related - when you hook the rod, make sure it's still connected to the ring around the base of the distributor shaft..... if you need pictures, I'll go grab a couple ... no worries though - I've learned this lesson the hard way (and had all the things that could go wrong I've listed above)....
 
Stoneshrink, I think you have what the vacuum advance does backward. When you step on the gas vacuum drops therefore the vacuum advance canister RETARDS the timing to avoid ping. It allows alot of advance at cruise for improved economy
 
okay, I see I wasn't terribly clear. Without the vacuum advance working, your motor will be sluggish. At idle, or at low-throttle positions the vacuum advance is working by advancing the timing - thus when you set your timing, you must remove the vacuum hose from the distributor and plug the line.

However, I stick by what I've said before, look for holes in that system (or, though I really doubt it given what you've said) make sure that your vacuum advance is to the hole that has vacuum at idle but not vacuum all the time.
 
Thanks again to all

I have yet to have the time to check everything, I hope to do so tomorrow. I am hoping to have a friend over that know more and have a vacuum gauge.
When the timing was set I know the vacuum line was left on so that I will check.

Here is something I found out they I need answered. The person that timed it the first time was tinkering with the carb and NOW told me that he unspring the choke on the side of the carb. He twisted it back on and screwed it back on without telling me. Could this be part of my issue? If so how do I know how to fix it. The secondary seems tight when moving it.
 
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