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I just got a quick question. Did 82 T/As with LG4s come with vacuum advance stock? When the shop changed the main block to a 350, it looks like the vacuum advance was removed or the dist was replaced. I ask this because when I was checking it today, I found a loose "hose" (It looks like a rubber plug at the end) at the rear where the distributor is. Is it possible that they removed the vacuum advance? Would there be any drawbacks? What other way would it advance if not vacuum and what should I look for?
Also can anyone tell me how to read the timing marks? I found the notches, but they are not centered, they're more to the driver side.
This is my first time doing timing so sorry for the stupid and long questions. Using this as reference http://www.youtube.com/watch?v=UYGU7mTwsZc.
Oh, and my EGR stuff is disconnected and plugged if that matters. Stock intake.
Andddd... it is misfiring.
Thanks
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Ok, I'm not crazy then, haha thanks. The pic attached is the wire I was talking about. Any idea where it goes?
I also got a timing light, Actron CP7529, which I'm having problems figuring out. I started to check what the current timing is and I get a weird number. I followed the directions, connected everything right. I marked the notch with white out and cleaned the timing marks. I flashed the light till the white out matched with 0* TDC.
I got "77" to make the marks match at ~950rpm. Which was 0* TDC. I don't have a great idle...
With the same "77", I revved to 2000rpm and the line moved to 8*BTDC.
So does that mean my timing is advanced 77*? I turned the distributor back and forth and the white out moved but not that much to make it something like 12* advance.
Any ideas?
Looks like the vacuum line that runs the HVAC vacuum servo controls under the dash. Look in the "carburetors" forum on this website for some vacuum routing diagrams that should help you out.
Can't figure out what you're doing wrong with the timing light, but you need to disconnect the timing advance connector before checking/setting your initial timing. It's a flat 4-pin connector coming out the back of the distributor over the tranny bellhousing. Disconnect that connector before checking your base timing. Stock setting is 0* for an LG4. Most have found you can bump it up easily 4* over stock (4* BTDC) or more for better power with little or no downside.
__________________ 90 Chevy 454SS truck. Out with the wheezing TBI dumptruck engine, in with a nasty little AFR-headed solid cammed 454 taken "back to basics" with big Holley 4bbl, single plane intake, big headers, loud exhaust, and nothing remotely close to emissions compliance or good fuel economy. Loud, dangerous, anti-social and lots of fun.
78 Malibu. Inherited from my Grandomther with only 35K on the odo! 13.4 @ 107 with mild N/A 383. With Weiand 142 blower installed....... not quite so mild. Orignially shooting for 11.99 on street tires, but mid 12s appears to be the best it's gonna do- nowhere near enough traction.
Oh, good call on the 4pin connector. I realize now I didn't disconnect it even though I looked at the manual 20 times. Would that do the trick and not give me wacky numbers?
I'll look for those diagrams.
edit:
searching through found me this line-
naf
"The plastic vaccuum line (plastic allows the sensor to read more accurately because it won't flex like rubber vaccuum lines) from the map sensor (near master cylinder) should be run through convoluted tubing with part of the wiring harness, up from behind the dist into the rear of the carb."
sounds like i found what it is
Hooked up that vacuum line so that's all good.
Disconnected the 4pin and tried timing again. The idle is down to around 750-850 from 1050+, but the car shuts off after sitting idling for a bit. The timing light is saying the current ADV is 55.3. Made a diff, but should be something smaller shouldn't it? Ideas? I'll have to see if its still misfiring on the way to school.
ADDED:
Don't know if it's misfiring. The check engine lights not blinking anymore, but if I'm at speed and floor it, the car feels like it stalls and then continues. It does that mostly in 3rd/4th gear. Ideas?
did some research and it seems i may have a vaccum problem. my main problems highlighted in green.
the screw that doesnt do anything is the one on the top center of the carb.
Quote:
So how do you know when a vacuum leak is causing a problem? If the engine is experiencing any of the following symptoms, a vacuum leak is probably responsible:
Too fast an idle speed
. If an engine without computerized idle speed control is idling too fast and refuses to come down to a normal idle speed despite your best efforts to back off the carburetor idle speed screw or air bypass adjustment screw (fuel injection), air is getting past the throttle somewhere. Common leak paths include the carburetor and throttle body gaskets, carburetor insulator spacers, intake manifold gaskets, and of course, any of the engine's vacuum fittings, hoses and accessories. It is even possible that leaky O-rings around the fuel injectors are allowing air to leak past the seals. Another overlooked item can be a worn throttle shaft.
A rough idle or stalling. A performance cam with lots of valve overlap can give an engine a lopping idle, but so can a vacuum leak. A really serious leak can lean the air/fuel mixture out to such an extent that an engine won't idle at all. An EGR valve that is stuck open at idle can have the same effect as a vacuum leak. So too can the wrong PCV valve (one that flows too much air for the application), or a loose PCV hose. The rough idle in these cases is caused by "lean misfire." The fuel mixture is too lean to ignite reliably so it often misfires and fails to ignite at all. Lean misfire will show up as elevated hydrocarbon (HC) readings in the exhaust, enough, in fact, to cause a vehicle to fail an emissions test.
Hesitation or misfiring when accelerating. This may be due to a vacuum leak, but it can also be caused by a weak or inoperative accelerator pump in a carburetor, dirty injectors, or even ignition problems such as a cracked coil, worn spark plugs or incorrectly gapped plugs.
An idle mixture that defies adjustment. When setting the idle mixture adjustment screws on a carburetor, the idle speed should start to falter as the adjustment screws are turned in to lean out the mixture. If the screws seem to have little or no effect on idle, you have either got a carburetor problem or a vacuum leak.
Disconnected the 4pin and tried timing again. The timing light is saying the current ADV is 55.3. Made a diff, but should be something smaller shouldn't it?
With the 4 pin connector disconnected, or reconnected?
Also can anyone tell me how to read the timing marks? I found the notches, but they are not centered, they're more to the driver side.
In an 82, 305, 4bbl carb engine the timing marks should be straight down behind the water pump (12:00 position). If yours are over to the side next to the water pump leg (1:30) position that could explain quite a bit of the difference. There is about 40* difference between the two timing tab positions. That would mean 40* MORE timing advance showing than actual.
This is assuming that somebody used the original 12:00 timing mark position balancer with a 1:30 position timing tab.
Any chance somebody monkeyed with the engine before you got it?
__________________ 90 Chevy 454SS truck. Out with the wheezing TBI dumptruck engine, in with a nasty little AFR-headed solid cammed 454 taken "back to basics" with big Holley 4bbl, single plane intake, big headers, loud exhaust, and nothing remotely close to emissions compliance or good fuel economy. Loud, dangerous, anti-social and lots of fun.
78 Malibu. Inherited from my Grandomther with only 35K on the odo! 13.4 @ 107 with mild N/A 383. With Weiand 142 blower installed....... not quite so mild. Orignially shooting for 11.99 on street tires, but mid 12s appears to be the best it's gonna do- nowhere near enough traction.
In an 82, 305, 4bbl carb engine the timing marks should be straight down behind the water pump (12:00 position). If yours are over to the side next to the water pump leg (1:30) position that could explain quite a bit of the difference. There is about 40* difference between the two timing tab positions. That would mean 40* MORE timing advance showing than actual.
This is assuming that somebody used the original 12:00 timing mark position balancer with a 1:30 position timing tab.
Any chance somebody monkeyed with the engine before you got it?
The monke...*cough* mechanics at the workshop. . The marks on the side next to the water pump (1:30) is what I'm using. I'll check right now to see if there's a (12:00) tab. If there isn't, I have to subtract 45* from my timing light (360/12=30, 30*1.5=45)?
Quote:
Originally Posted by Jeffs82TA
Looks more like the MAP sensor line.
Yep. It was. Or the equivalent for carbs. Description in previous post.
Quote:
Originally Posted by five7kid
Sounds like the 350 has a 12 o'clock damper and 1:30 o'clock tab.
Sounds like you guys are spot on lol. I think it has a different waterpump than my 83's 350.
I'll look into what you guys are saying.
Thanks for all the input so far.
Water pumps are the same. No 12:00 mark on either of the cars. Both 350s with 1:30s.
Ok, now I have the timing set to 51* with connector off. It was 55.8* before with connnector off. That would mean it's 6* advanced correct? Is that the max the car can tolerate? What should I set it to?
I used the (1:30)'s 0* as a base and made 51* on the TL equal to the zero mark.
Edit- Should have re-read and saw that it's 4* BTDC
Quote:
Originally Posted by "Damon"
Stock setting is 0* for an LG4. Most have found you can bump it up easily 4* over stock (4* BTDC) or more for better power with little or no downside.
So that means 4* adv or retard, as in on my TL it should read 49* or 41*.
45* being equal to 0*.
It's not a full 45. More like 40. I wouldn't guestimate in this case. You can buy a bolt-on 12:00 position timing tab from Summit and other places for under $10. Link:
If it's the stock balancer it's the smaller 6-3/4" unit (sometimes called 7"- it's the same thing).
One other thing- is there any chance your balancer has slipped the outter ring? That can happen when they get some age and miles on them. Then the timing mark is worthess for setting timing.
Pretty sure it's the stock balancer. I could see the remanants of the original engine's blue paint. I don't think so since the engine was put in last year.
Also, my timing mark jumps around like this guy: http://www.cadillacforums.com/forums...ing-472-a.html
I can get a general idea of where it is, but it does move around. I need another set of eyes to verify if what I'm doing everything right. I don't know anyone else that can do this stuff. Plus the mechanics around here suck and/or are too expensive.
A slipped balancer won't cause the timing to float around while you have the gun on it. It'll be a slow, gradual change in the position of the timing mark the more you drive it. In extreme cases the outer ring can move rearward and start scraping the timing chain cover.
If the timing floats around a few degrees at idle (with the timing connector unplugged so it should be constant) then you've either got a worn out timing chain (not a huge deal- address it when you rebuild the motor in the future) or the teeth on the distributor gear are chewed up (which needs to be addressed right away and could possibly have already chewed up the teeth on the cam, which would require a new cam to fix).
Pretty sure nothings scraping around there. The thing is, it's not a slow gradual change. It jumps around like the spark's missing. Every time it hops around, the engine makes a different sound. I don't know what's considered a few degrees, but it can be completely at one side of the timing marks, then can be at the other. I'm hoping it's something little at the dist, like a coil or idk. Just not something huge as I have classes to worry about.
Summit has a house brand true roller chain set for about $35 the last time I checked. That's about the cheapest timing chain set I've found that actually has good quality. When you get into the $20 cheapies they usually stretch like salt water taffy in only a few hundred miles of running.
Both are summit brands.
"Do it once, do it right" with the double roller? I'm not sure if you meant single or double roller will be fine with the stock cover.
Both are summit brands.
"Do it once, do it right" with the double roller? I'm not sure if you meant single or double roller will be fine with the stock cover.
They are both double roller. The first one is for non-roller lifter camshaft, the 2nd one for roller lifter camshaft. You want the first one, I believe, unless your 350 is '87-later passenger car.
They are both double roller. The first one is for non-roller lifter camshaft, the 2nd one for roller lifter camshaft. You want the first one, I believe, unless your 350 is '87-later passenger car.
Gotcha. I guess I shouldn't be posting when I'm about to pass out.
I'm pretty sure it's a pre-87 350. I'll go with that. Thanks. Will update as it goes.
. The marks on the side next to the water pump (1:30) is what I'm using. I'll check right now to see if there's a (12:00) tab. If there isn't, I have to subtract 45* from my timing light (360/12=30, 30*1.5=45)?
