1974 2.0l w/dual 34ICTs having blowby Options

[justjoel]

Finally got my project 914 on the road and it's running really good with dual 34ICTs but I started noticing burning oil smells in the cabin. Now it does have a minor oil leak, I believe from the distributor o-ring and I will be addressing that but I realized it was blowing smoke/oil from the crankcase breather and the cylinder head vents. I installed a catch-can where I routed the crankcase breather and cylinder head vents to and have a filter on top of the catch can but it's still smoking out the filter and getting into the cabin where it proceeds to give me a nice migraine after 20-30 min drive.

I believe I should remove the top filter and run a line into the carbs for the vapors to be sucked back into the system, is that correct? Will that gum up my carbs?

Now the car sat for probably 20+ years prior to me picking it up and fixing it but it fires right up, no issues and runs "cool" and strong. Compression tests out good, valves have been adjusted to the best of my ability and there is no smoke out of the tailpipe. How concerned should I be about blowby? When I open the oil fill cap there is quite a bit of smoke and pressure coming out. I am unfamiliar with aircooled engines but I would think the piston rings are worn. Should I be thinking rebuild time? As in new pistons, cylinders, rings etc. If so, what "while you're in there" things should I start budgeting for?

Please let me know your thoughts.
Thank you.

[Ninja]

Most likely oil is leaking on the exhaust/heat exchangers.

They are bad about the pushrod tube O-rings.

Makes for nasty smells!

I wouldn't run that. Lots of "got it running after XX year threads" end up with a dropped valve/broken spring which equals a complete rebuild.

I have a 75 with 31K that hibernated for 33 years (1988 inspection sticker).

It also runs OK.

I will not run it again before removing the engine, replacing ALL of the rubber seals and replacing the valve springs.

Some (at least two) of the valve springs sat open (compressed) for decades. These are the springs I worry about.

The parts are not seriously expensive until you drop a valve.

I know my advice sucks but $300-$500 today could save 3000+ two months from now.

This is not 914 specific. Valve springs SHOULD be replaced every 20-30 years on anything.

[930cabman]

(IMG:style_emoticons/default/welcome.png)

Great start to the fun of 914's and welcome aboard

If the compression checks out and there is little/no smoke from the tailpipe, I would say the rings are ok

After a 20 years sleep (IMG:style_emoticons/default/beer.gif)

[justjoel]

Thanks for the input. I feared it'd be a rebuild. I was hoping to enjoy the car this spring and summer before tearing further into it. It's already spent 6 months on jackstands getting the hell hole fixed up. But you're probably right. Delaying the inevitable engine rebuild.

[justjoel]

Most likely oil is leaking on the exhaust/heat exchangers.

They are bad about the pushrod tube O-rings.

Makes for nasty smells!

I wouldn't run that. Lots of "got it running after XX year threads" end up with a dropped valve/broken spring which equals a complete rebuild.

I have a 75 with 31K that hibernated for 33 years (1988 inspection sticker).

It also runs OK.

I will not run it again before removing the engine, replacing ALL of the rubber seals and replacing the valve springs.

Some (at least two) of the valve springs sat open (compressed) for decades. These are the springs I worry about.

The parts are not seriously expensive until you drop a valve.

I know my advice sucks but $300-$500 today could save 3000+ two months from now.

This is not 914 specific. Valve springs SHOULD be replaced every 20-30 years on anything.

Well I was thinking it was oil getting on my exhaust but I already replaced all the pushrod seals, the oil cooler seals, rear main seal... it's got a slow leak from above the oil filter area so I was thinking it was distributor shaft seal leaking. I have one sitting in the garage ready for replacement before I realized the blowby was happening. I watched Han's Garage on Youtube replace the springs with the heads on and it didn't seem too terrible. I'll have to add it to the list. If I'm going to replace the pistons, rings and cylinders I'll definitely replace the valve springs and guides while I'm in there. It's just time and money right....

[930cabman]

just time and money, how far and fast do you want to go?

stick with it, I was a 356 and 911 guy for many many years, got bit by the 914 bug in 2020, sold the 356 and now have 5 914's

they are a blast, especially if you can fit one with a /6

[justjoel]

just time and money, how far and fast do you want to go?

stick with it, I was a 356 and 911 guy for many many years, got bit by the 914 bug in 2020, sold the 356 and now have 5 914's

they are a blast, especially if you can fit one with a /6

That's awesome. I am envious because I'd love to own a 356 or a 911! I can ONLY afford the 914 haha. Well I have another entry level Porsche, the Boxster as well. But! I really love driving the 914 and the sense of accomplishment from resurrecting this thing from the dead. It really should have been a parts car but I refused to let it die, even though it feels like it wants to die sometimes.

How does the 914 compare to driving a 356 or a 911?

I think I will try ducting the crankcase vent into the carb and see if that alleviates the headaches when I drive it. It's not the right fix but maybe the fix I can afford for now haha.

Thanks for the response!

[914sgofast2]

Excessive blowby on an engine that has sat for a long period of time often indicates that the oil control rings have gotten gummed up. Change the oil more frequently and drive it .

[930cabman]

Excessive blowby on an engine that has sat for a long period of time often indicates that the oil control rings have gotten gummed up. Change the oil more frequently and drive it .

I have seen this before, wondering if running with light (10W) oil would loosen up any "stuck" oil rings. OP claims no smoke from the tailpipe

[justjoel]

Excessive blowby on an engine that has sat for a long period of time often indicates that the oil control rings have gotten gummed up. Change the oil more frequently and drive it .

I like your thought process. What are your thoughts on soaking the cylinders in berrymans b12 like the Toyota folks have to do? Basically putting it down the spark plug holes to free up the rings. I'm down to try anything before tearing the engine apart and rebuilding it. I think that is inevitable but I'd like to get a few months of driving out of it. Thanks for the feedback!

[justjoel]

Excessive blowby on an engine that has sat for a long period of time often indicates that the oil control rings have gotten gummed up. Change the oil more frequently and drive it .

I have seen this before, wondering if running with light (10W) oil would loosen up any "stuck" oil rings. OP claims no smoke from the tailpipe

I will certainly give this a shot. I am running 15w-40 diesel oil currently so maybe the lighter oil will help. Thanks!

[Spoke]

I believe I should remove the top filter and run a line into the carbs for the vapors to be sucked back into the system, is that correct? Will that gum up my carbs?

I've run the crankcase vent hose to both carbs on my car. Works fine sometimes. Very little oil noticed on top of the carbs. Had this for several years.

When on the gas, I get no fumes in the cabin. However on long decels with carb butterflies closed, the crank gas has nowhere to go and floats out of the carb air cleaners and back into the cabin. I shut off the heat while on long decels.

[justjoel]

As an update, I pulled the engine to replace the front main seal and oil pump gasket to fix some front engine oil leaks and found that the timing marks I assumed were TDC were slightly off. I'm not sure if this was a replacement fan or what but I couldn't see the notch with it in the car. I replaced the seals (still leaks oil) but created a mark on the fan so I can see it when timing the car. I also upgraded from 34 ICTs to 40 IDFs I found on FB. Got everything dialed in, valves adjusted to "new" TDC and set the timing to 30° BTDC and it ran great with no smoke or noticeable blowby... for exactly one day. I mean it felt powerful, running and idling great.

Let it sit for a day, tried to start it.... dead. Cranks but won't start. So I started to try to figure it out. Checked spark, has it. Checked fuel, has it. Checked compression... not great but has it. #1: 80psi, #2: 105 psi, #3: 85 psi, #4: 95 psi -- definitely tired but has compression so valves are closing. I got it to fire up and it ran rough. I stupidly took it out for a quick spin in the neighborhood and it was cutting out like a dead miss or something under load. Limped it home.

Decided maybe it was ignition related so I replaced everything. New coil, distributor, cap, rotor, plugs, wires. It's all new. Went back to point ignition from electric ignition. I checked the oil, doesn't smell like fuel, thinking maybe the carbs were leaking fuel and flooding the engine.

It fired up but ran like crap. Hunting idle, wouldn't stay running...
Today. No start again.

What the heck do I do? I know it's tired and needs a rebuild but it should still start. Hesitant to throw money at a rebuild if it's something worse (or easy).

This isn't a show car and it isn't worth a ton - I pulled it out of a shed and am low buck restoring it to just drive and enjoy. I have never owned a carbureted car or an air cooled vw... so I'm trying to learn as I go but this one has me stumped and very frustrated. I don't understand what would have changed from one day to the next, running great to not running at all.

The only thing I can think of is that maybe I wiped out the camshaft having the timing off originally? Or I wiped it out with my "new" timing? Or?? I don't know where to go from here. Any input would be greatly appreciated.

[Shivers]

As an update, I pulled the engine to replace the front main seal and oil pump gasket to fix some front engine oil leaks and found that the timing marks I assumed were TDC were slightly off. I'm not sure if this was a replacement fan or what but I couldn't see the notch with it in the car. I replaced the seals (still leaks oil) but created a mark on the fan so I can see it when timing the car. I also upgraded from 34 ICTs to 40 IDFs I found on FB. Got everything dialed in, valves adjusted to "new" TDC and set the timing to 30° BTDC and it ran great with no smoke or noticeable blowby... for exactly one day. I mean it felt powerful, running and idling great.

Let it sit for a day, tried to start it.... dead. Cranks but won't start. So I started to try to figure it out. Checked spark, has it. Checked fuel, has it. Checked compression... not great but has it. #1: 80psi, #2: 105 psi, #3: 85 psi, #4: 95 psi -- definitely tired but has compression so valves are closing. I got it to fire up and it ran rough. I stupidly took it out for a quick spin in the neighborhood and it was cutting out like a dead miss or something under load. Limped it home.

Decided maybe it was ignition related so I replaced everything. New coil, distributor, cap, rotor, plugs, wires. It's all new. Went back to point ignition from electric ignition. I checked the oil, doesn't smell like fuel, thinking maybe the carbs were leaking fuel and flooding the engine.

It fired up but ran like crap. Hunting idle, wouldn't stay running...
Today. No start again.

What the heck do I do? I know it's tired and needs a rebuild but it should still start. Hesitant to throw money at a rebuild if it's something worse (or easy).

This isn't a show car and it isn't worth a ton - I pulled it out of a shed and am low buck restoring it to just drive and enjoy. I have never owned a carbureted car or an air cooled vw... so I'm trying to learn as I go but this one has me stumped and very frustrated. I don't understand what would have changed from one day to the next, running great to not running at all.

The only thing I can think of is that maybe I wiped out the camshaft having the timing off originally? Or I wiped it out with my "new" timing? Or?? I don't know where to go from here. Any input would be greatly appreciated.

I have 40 idf’s and over the years I have become a jet cleaning expert. Try cleaning the jets high lighted in red. If this clears it up, add a good fuel filter and since you really don’t know those carbs I’d clean them. A single bristle from a wire brush works great for cleaning the jets, it doesn’t want to stay bent and springs back to straight.