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Discussion Starter · #63 ·
Have you even checked fuel pressure?
You might not need a regulator.
Look in the carb while it’s warmed up and idling. If you see any raw fuel then you need to fix that. A simple float level adjustment might fix it.
An alternative to a regulator is a fuel pump rated at 5.5 psi. Edelbrock has one.

You’ll likely shoot me if I told you I sold my 70 chevelle LS6 4 speed to buy the trans am. The trans am was traded off in 82 for a truck.
OK, finally got to look at that today.
when warmed up as you said, there is no drops coming from those 2 nozzle's.
But when its cold and its warming up there are lots of drops from those same 2 nozzle's.
Also when its warmed up, and you press the accelerator, then some drops do fall from these nozzles,
and obviously from the lower 2 squitter jets too (not the technical term).
So is that all as expected, or an issue?
Thanks
 

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When it’s warmed up it’s hard to see a tiny amount dripping. Drips are still there though.

the dripping while cold tells you it’s flooding a bit.
‘Seeing fuel when you press it shows the accelerator pump is working. That’s normal.
‘Try this.
when cold and dripping squeeze the fuel hose with some pliers. That’ll act like a regulator. If the drips stop you know it’s a pressure problem or a float level problem.
 

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Discussion Starter · #65 ·
Also there is a T in the vacuum line close to the distributor pod and there is nothing connected to it.
See the T in the picture, its in the centre roughly. Its on the same vacuum line as the PCV valve that is T 'd into the carb.
When I hold my finger over the T hole the idle goes from 650rpm to 800rpm.
It seems to tick over nicely at 650rpm, so not sure if I should cap it or leave it open.
But if left open then surely this defeats the whole purpose of the vacuum???
This vacuum **** is frustrating.
Should i just rejig it and have 1 line from pod to carb, and a separate line from PCV to carb?
And what if my idle revs increase to 800 then?
Automotive tire Motor vehicle Hood Grey Automotive exterior
 

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It’s a vacuum leak.
you need to cap it.
easier to run a new line to the carb.
the two caps on the front of the carb are used for vac advance.
the left one is ported vacuum. Ported means no vacuum until throttle opens.
the Right cap is manifold vacuum. That means vacuum all the time.
if you plug into ported your idle should stay at 650.
also run a new line for the pcv.
 

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Discussion Starter · #67 ·
It’s a vacuum leak.
you need to cap it.
easier to run a new line to the carb.
the two caps on the front of the carb are used for vac advance.
the left one is ported vacuum. Ported means no vacuum until throttle opens.
the Right cap is manifold vacuum. That means vacuum all the time.
if you plug into ported your idle should stay at 650.
also run a new line for the pcv.
Thanks, makes sense, I will try it.
What about my earlier question about vent cap element instead of a pipe going into the air filter housing?
 

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Discussion Starter · #70 ·
Sorry had other family issues to deal with.
Yes I mean a valve cover breather like in the picture attached.
I was going to replace the clean air intake hose that goes from the air filter to the valve cover
(its the valve cover on passenger side - not valve cover with PCV).

Photograph White Camera accessory Black Cameras & optics
 

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The picture shows a filthy, unkempt engine. I assume it looks the same internally. I’d say your drips are the result of excessive blow-by caused by internal wear.

Anything short of pulling it out and rebuilding it is like wearing rubber gloves because your pen leaks ink.

Bogie
 

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Discussion Starter · #72 ·
The picture shows a filthy, unkempt engine. I assume it looks the same internally. I’d say your drips are the result of excessive blow-by caused by internal wear.

Anything short of pulling it out and rebuilding it is like wearing rubber gloves because your pen leaks ink.

Bogie
I'd say if your pen leaks and you have to go 4,000 miles to get another one, wearing gloves is a good idea.
Correct it is an unkept engine, so I am trying to tidy it up. The car is 40 years old, I have it a few months.
You didn't answer my question about replacing the clean air hose with a breather vent.
And I thought we already agreed to fix the known issues before 'pulling out' the engine.
I mean, you say it like its nothing. And there is are no drips, just trying to stop oil vapours going into air filter.
I will write a summary of where i am with it now, so your up to date. Thanks Bogie
 

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Discussion Starter · #73 ·
Vacuum
The PCV valve to the carb vac port was T'd to the distributor pod,
and T'd to the air filter housing temp sensor (not used) and was leaking vac.
The vac ports for the dist pod and the Auto Tran were both rubber capped.
The rubber cap on the Auto Tran port was badly cracked and leaking also.
Disconnected all and started again.
It's a stick shift, so I put new cap on Auto Tran port.
Ran separate hose from dist pod to ported vac.
And separate hose from PCV to center vac port.
Now its idling at 600rpm and sounds nice.
The cold start fast idle was running at 2500rpm, I adjusted that down to 1500rpm.

Air-Fuel
There has always been a smell of gas in the garage from it and it has no fuel regulator.
So distinct possibility of flooding. Had black tailpipes, so know its running rich.
Regulator ordered and will take 2 weeks from USA. (Holley regulator and dry guage).
The air filter is blocked and smells of oil, as does the air breather hose filter. (Thinking of replacing
the breather hose with a valve breather vent - to stop any future oil vapour getting to air filter)???
Ordered AcDelco air & oil & fuel filters, will also take 2 weeks from USA.

Blow-by
Looked at a Youtube video about Blow-by and followed his instructions for checking.
He had some small amount of oil spit onto a sheet of white paper on his, saying that's ok at start-up.
Air filter out - there is no smoke from the open oil filler or dipstick, at cold start or when warmed up.
There is no oil spits (onto a sheet of white paper) from oil filler or dipstick openings (cold or warm).
There is practically no smoke from exhaust, definitely no puffs of black or blue and no bad smell.
There is no obvious oil leaking and none on the garage floor.
There is some black soot spits on the floor at tail pipes, where its parked everyday.
There is black deposits on plugs. (not sure what style, E3 looks good?? Can get Denso T16PR-U)
Took out air filter and Car runs good, (but haven't gone far - until I get new air filter).
Seen another Youtube video where they had a air filter that was too small and it Dyno'd 80HP less.

Whats going on?
Johnsongrass1 already confirmed that a badly blocked air filter could drag oil vapour in,
and as the air filter and air breather hose filter has oil on them, this makes sense.
Also if it is flooding and washing some oil, wouldn't that make more oil vapour?
And if there was 2 vac leaks, couldn't that have blacked around intake manifold with oil vapour?
If there was significant blow-by won't it have shown up in the oil filler and dipstick openings??

My plan is to replace all filters, install fuel regulator, fix vac leaks (done), and then drive it and see.
It could still be a horror show, but i'd like to see what happens when these known issues are fixed.
What u think of my findings? (be gentle - LOL)
I have learned a lot from this Forum (well a lot more than I knew beforehand), thanks to all!
 

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If there is excessive blow-by from worn rings, the PCV valve will not be able to handle the volume during normal routine driving and pressure will build up inside the crankcase. The only place blow-by has to go is through the PCV valve or out that port on the valve cover and into the stock air cleaner through the little foam crankcase filter in the side of it. Simply put, if you have oil in a stock air cleaner (that is atill hooked to the valve cover), then either the PCV system is malfunctioning or the engine has excessive blow-by. The air flow is supposed to be from the air cleaner into the valve cover and then out of the crankscase through the PCV valve to have the vapors burnt. It is supposed to be operating at a very slight vacuum, and this helps keep oil inside of the engine.

I have seen engines with enough blowby that you can see the vapors coming out of the valve cover tube at idle, even with a functIonal PCV valve. If your engine is like this, you will have to put up with the oil useage. It is shot and blowing oil out of everywhere..

But if you hold your finger over the tube from the valve cover to the air cleaner and hold the engine at 2000 rpm steady, and can feel some vacuum there may be some hope? If you can, then what about at idle? This is kind of a very simple substitute for the leak down test I previously suggested in post #38.

Definitely fix the vacuum leak on the line to the distributor. I thought that port went to a valve on the air cleaner. Maybe not. Check the vacuum schematic. It's been 40 years since I was working on these in the dealership.
 

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Discussion Starter · #75 ·
I took that 3/4" hose off the valve cover when running and nothing spit out, but didn't check it at 2000rpm.
How much vacuum should there be at 2000 and at idle.
Light touch or can you give me some idea of what it should be. Thanks
 

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To test for any oil mist being pulled into the intake with the pcv and hose in normal running I’ve used a clear hose instead of the normal black hose.
Only used for about 500 miles like that. Just as a test. Clear hose can be found at a plumbing or hardware store.
You might find your pcv valve is bad or the wrong one. Or you don’t have an oil baffle where the pcv is on the valve cover.
 

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I took that 3/4" hose off the valve cover when running and nothing spit out, but didn't check it at 2000rpm.
How much vacuum should there be at 2000 and at idle.
Light touch or can you give me some idea of what it should be. Thanks
Not much vacuum - just a touch. Just enough to feel a little difference as your thumb is pulled off. Leave your thumb over the hole for maybe 10-20 seconds to let vacuum build up. Never quantitated it. If the hose was connected to the air cleaner and air cleaner didn't have oil in it, you may be fine on blow-by.
 

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The oil vapor is intended to go into the aircleaner. GM uses a PCV valve which utilizes manifold vacuum to draw crankcase vapor into the intake manifold which might terminate at a fitting on the carb that has passages exposed to the intake routed in the casting ending below the throttles or the valve may connect to the intake itself.

The opposite valve cover as factory equipped would have had an oil cap that is closed to the atmosphere but has a nipple for a hose attachment that connects to a nipple on the air cleaner. This routing keeps allows to blow vapor into the aircleaner when manifold vacuum falls as the throttle is opened dropping manifold vacuum while opening the throttle increases blow by, a result of increased displacement being used via increased RPM and increased cylinder pressure. So opportunity (RPM) and force (crankcase pressure) drives more blow by than the PCV valve can manage. The factory air cleaner needs a flame arrester so backfires won’t use this part of the system as a route to ignite crankcase vapor which is mostly unburnt fuel escaping around the rings. There is enough power to blow the valve covers and sometimes the oil pan off the engine. The factory has used two systems of return one outside the air filter using it as a flame barrier the other inside the filter element using metal directors and screens to redirect and quench the flame. There is an oily component in the vapor that makes a mess of the filter element when introduced from the outer side.

Oil droplets are removed inside the valve/rocker cover by a ventilated box under where the PCV valve connects and where the cap connecting to the aircleaner connects. Oil replacement is usually through a third or even fourth cap that is open to the inside of the valve cover with no internal oil separation box. These caps, all caps, except the PCV valve nipple cap are sealed to the atmosphere. The Edelbrock vented cap you pictured is NOT how the factory built these. These vented caps are an air inlet for race engines that operate with either a crankcase vent pump or with header crankcase siphon vents that use the passing high speed exhaust to carry crankcase vapor out of the engine. It’s not that you can’t build with a vented cap but you’re gonna have a constant oily mess to wipe up.

So anything that is actively venting must have some sort of an oil separator this may be simply a box that has louvers on the outside. Inside there maybe nothing (not a good design), or baffles to spin the vapor so oil gets separated, or a mesh of metal or plastic that through turbulence separates oil from vapors. Do not be temped to use steel wool as it sheds small pieces into the engine, forever.

If it is pushing a lot of oil out with the blowby that indicates the rings are not functioning as needed. Here you have to differentiate ring functions. The top ring is a compression ring, it’s failure (there is a long list of reasons why) allows the pressures of compression and operation to escape past the other rings and into the crankcase this is classic blowby of unburnt mixture and products of combustion as in exhaust gases into the crankcase. The second ring does two jobs; it backs up the compression ring and fine wipes oil from the upper cylinder. When it is in failure you get oil consumption into the combustion chamber in one direction and/or with blowby in the other. The third ring is an oil scraper, in failure it leaves the cylinder walls saturated with oil which the floods the second ring beyond its capabilities of fine oil control then it and the now flooded top ring pump oil into the combustion chambers which you see as blueish smoke out the exhaust. Now another element that can contribute to the oil rings loosing control and for a lot of oil in mist and droplet form that the blow by can pick up is the blessings of a high pressure and or high volume oil pump, especially without a windage tray. This combination just floods the bottom end with so much oil that without a scraper and windage tray the rings are just overwhelmed. You will note the Gen III and up engines put an indexed oil spray on the inside bottom of the pistons to cool them. This oil is controlled as to where it strikes the piston and these engines use factory installed windage trays and scrapers to pull the mist and splash out of the circulation so the rings aren’t drowned in oil.

My observation of the filthy exterior and improper assembly was only to emphasize that you have your work cut out for you and not to expect that this is a diamond in the rough. You can expect this grubby build ethic extends to the inside and the more and deeper you dig at this thing you’re just going to find more rough. That means you are going have to do a lot of research on top of the gritty work. It appears to me that this is a learning experience for you. Being up front with you; while you need to clean this mess up, don’t expect that this effort will solve the internal problems that are likely to end with that engine coming out for a major overhaul of the internals.

Then to add insult to injury if this is an automatic transmission you can expect that it would not last long behind a fresh engine. Hot rodding is just like that every fix begets another, so you are into a long term project that is a substantial undertaking in the US where parts, tools, facilities and experience are immediately at hand and usually at reasonable cost. Ireland is going to make what is already a tough job just that much more difficult so your psyche has got to be in this along with your bank account and family.

Bogie
 
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