I would like to see you fabricate a PCV system as they make the engine run better as well as cleaner, but, you are 100% correct that you do not want to run all to a single cylinder.
I would like to see you fabricate a PCV system as they make the engine run better as well as cleaner, but, you are 100% correct that you do not want to run all to a single cylinder.
Me too.
How separate does pcv have to be from vacuum?
In reply to paddygarcia :
I have been experimenting recently with a Weber carb Lotus Twin Cam, a fresh rebuild, and so far I have not found "far enough"
I have been using the same PCV valve that is OEM to your Volvo. My valve to vacuum manifold run is noteably shorter in vertical and horizontal dimension than yours would be on the Volvo. I also do not have the space for the separator can that the Volvo has beneath the valve. I put 1/16 NPT fittings in all 4 intake runners and led them into a 6 way manifold block I bought from McMaster-Carr. I would try the same technique on the Volvo. Sorry no photos. My partner in crime may have some, I'll post them if he does.
Sounds familiar!
I tried plumbing vacuum for an eventual efi project but it's plugged right now. Maybe attempt #2 should be pcv?
In reply to paddygarcia :
You are 1/2 way there. I ran 4 separate hoses to the vacuum manifold that on your engine could easily be bracketed off of the 2 upper intake manifold studs in the center. I think this is the manifold I used https://www.mcmaster.com/5469K131 .
Thanks - I remember looking at that one when putting this mess together. Ideally everything can stay mostly out of sight.
Jenvey used some spacers to get vacuum signal on the Aston with FI. If I did similar when its FI time (throttle bodies are on the shelf) the PCV would come up from the bottom in the middle of the runner and vacuum from the top/side of the carb end of the runner.
EDIT: maybe I should have RTFM, there are bosses for vacuum underneath the throttle bodies. Problem solved, my plumbing can be for PCV.
Works been a little busy, but I got some shop time in. With a little drilling I was able to use a 9mm empty as a restrictor. Might add a PCV valve, too.
In the 2 steps forward, 1 step back department, this week:
I was stoked to find a place a few towns over that rebuilds radiators. Less stoked today to see that it's leaking from the core. It was actually only leaking a little bit from the top tank when I sent it over there, should have let sleeping dogs lie. $466 later a new rad from VP is on the way.
Well, there's your problem right there. First pic is the old rad filler cap, with the nipple that was run to the overflow/pressure tank. Second is the NOS factory cap I had to buy because the Stant didn't fit on the new rad. That's because it's the wrong cap and doesn't allow the tank to communicate with the radiator unless the cap popped @ 15psi. Moreover, it compresses so far in the neck that I think it doesn't actually open. Which might be a reason the old rad leaked.
The NOS cap is used only to fill the rad, and the tank has the pressure cap.
$500 lighter I now have a new 3 row radiator that's set up correctly, look forward to driving this weekend.
A shakedown run on the weekend showed that the 123 Ignition dizzy was programmed a little too aggressively so I dropped it back to 32 degrees total advance.
Out today for a 50+ mile errand run, if I'm not back in a week send out the dogs.
All good yesterday, other than leaking valve cover gasket. Today I came home on a flatbed. The upper alternator bracket bolt backed out of the head. The lower bracket was kind of loose, so need to dig into that this weekend - thought it was shimmed to manufacturers spec.
Two bolts and one helicoil later everything's back together. Out today for a swim and coffee before work.
I really dig everything about this car.
Interesting reverse PCV. OEM setup is to suck in through the oil cap and out from the flame trap in the block into the intake. Any reason why you reversed it? I don't see why it wouldn't work, just interesting.
On my 4 door Amazon, it's been leaking badly out of the oil cap. I put on a new gasket, and went through the whole PCV system, still leaking oil. I'm about ready to try a new valve cover.
Volvo did it both ways - b18 and before took in air from the filler cap and exhausted the crankcase through the block. Early b20 the same, later b20 reversed. I did it this way to minimize hoses.
I don't think it matters as long as there's a filtered gozinta and a vacuum gozouta. Theres plenty of flow between crankcase and valve cover, pushrod V8s vent in one valve cover and out the other.
Regarding your filler/valve cover leaking, if the PCV is OK are you sure it's not being overloaded with blowby? Any leaks from the dipstick?
In reply to paddygarcia :
It could be blowby overloading, but it seemed to happen all of a sudden. Of course, that could be a blown ring or something. The car still seems to run fine, though I have never done a compression test on it. No leaks from the dipstick.
volvoclearinghouse said:In reply to paddygarcia :
The car still seems to run fine, though I have never done a compression test on it.
150 pounds or more and you're good.
It's been a pretty uneventful summer with the Smågris (Piglet). Get in car, Crack the choke, 3 pumps on the accelerator and drive pretty much anywhere. 500ish miles on the rebuild and it's turning out to be a nice, perky car.
The only thing I'm not keen on is the DCOE intake sound. I've loudified a few cars on the intake side and enjoyed the pipes. But some combination of the short straight intake path and engine compartment makes this one just sound percussive and buzzy. So how about we add an airbox?
There's not much space between carbs and inner fender but Pipercross makes a nice one that seems to be as narrow as they come. Measuring from carbs to fenderwell says there'd be about an inch of clearance, which might be enough. The crashing UK pound made it too hard to resist, especially once I found the dwg file for a base plate that I could modify for sendcutsend.
What I failed to consider was how far the baseplate comes down from the carbs, and thus how far down the airbox goes. The inner fender slopes into the center of the car and there just isn't room.
The factory and others hammered the inside fenderwell to make clearance for longer intakes and stacks. I wanted to make the clearance without painting, which Mr Asa and others disabused me of when I posted the question by itself. Have to think some more.
You're right about the plate of course, thanks. I designed it so should have put it on the right way!
I looked at a variant of those elbows made for BMWs, but there didn't seem to be enough clearance under the hood where it flattens out. Do you have pix of your airbox in place?
Thanks for the reference. I bought a set of Kooglewerks elbows, they'll do fine but I'll need to rework the air filter housing. That'll have to wait until I finish the 5-speed swap on this thing...
All good things must come to an end. We're making a major lifestyle change and a move overseas... With no cars.
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