Do a compression and leak down test before you do anything to see whats causing the plugs to oil foul. RICK
It's time
I finally got tired of the 350 in my Nova leaking oil from the rear main and using a quart every 200 miles. Started last night (Sunday) and finished this evening pulling it out. All the plugs are oiled up really bad, but #2 was the worst. I don't see how some even fired. The plugs only had about 1300 miles on them since I put them in new.
Tomorrow night I'll do the tear down on the engine and see just what is going on. It has to be mostly bad rings, but there were signs that the valve guides were sucking oil too.
Supposedly the engine was bored 30 over and a new Comp cam put in about 2000 miles before I got it, I have the bills from the NAPA dealer that PO had do the work, but there is no marking on the right front of the block deck where they usually stamp the block if it's been bored. It does have the 9 digit VIN number stamped there, as does the Muncie transmission, so it is a numbers matching car. The other code stamped there is V0402CNJ and the casting number is 3970010.
One question is how good are the 3927186 double hump heads. According one site they are 2.02/1.60 heads, but are they worth bringing them back up to snuff, or should I get a set of aftermarket heads? I'm going to put in a Comp Nostalgia Series cam that is a hydraulic version of the 327/350 30/30 cam. It does have a set of Comp steel roller tip rocker arms.
I will post some pictures as soon as I have time to set up an account on PhotoBucket of some similar site to post them.
Tomorrow night I'll do the tear down on the engine and see just what is going on. It has to be mostly bad rings, but there were signs that the valve guides were sucking oil too.
Supposedly the engine was bored 30 over and a new Comp cam put in about 2000 miles before I got it, I have the bills from the NAPA dealer that PO had do the work, but there is no marking on the right front of the block deck where they usually stamp the block if it's been bored. It does have the 9 digit VIN number stamped there, as does the Muncie transmission, so it is a numbers matching car. The other code stamped there is V0402CNJ and the casting number is 3970010.
One question is how good are the 3927186 double hump heads. According one site they are 2.02/1.60 heads, but are they worth bringing them back up to snuff, or should I get a set of aftermarket heads? I'm going to put in a Comp Nostalgia Series cam that is a hydraulic version of the 327/350 30/30 cam. It does have a set of Comp steel roller tip rocker arms.
I will post some pictures as soon as I have time to set up an account on PhotoBucket of some similar site to post them.
1 - 20 of 23 Posts
The 186 heads I believe come either way with 1.94 or 2.02 intake valves. They are a descent head, but old school now. They say the vortecs will outperform them also. The plus side to them is they have the accessory bolt holes in the 186's. Usually an old set of heads need a lot of money invested in them to bring them back.I finally got tired of the 350 in my Nova leaking oil from the rear main and using a quart every 200 miles. Started last night (Sunday) and finished this evening pulling it out. All the plugs are oiled up really bad, but #2 was the worst. I don't see how some even fired. The plugs only had about 1300 miles on them since I put them in new.
Tomorrow night I'll do the tear down on the engine and see just what is going on. It has to be mostly bad rings, but there were signs that the valve guides were sucking oil too.
Supposedly the engine was bored 30 over and a new Comp cam put in about 2000 miles before I got it, I have the bills from the NAPA dealer that PO had do the work, but there is no marking on the right front of the block deck where they usually stamp the block if it's been bored. It does have the 9 digit VIN number stamped there, as does the Muncie transmission, so it is a numbers matching car. The other code stamped there is V0402CNJ and the casting number is 3970010.
One question is how good are the 3927186 double hump heads. According one site they are 2.02/1.60 heads, but are they worth bringing them back up to snuff, or should I get a set of aftermarket heads? I'm going to put in a Comp Nostalgia Series cam that is a hydraulic version of the 327/350 30/30 cam. It does have a set of Comp steel roller tip rocker arms.
I will post some pictures as soon as I have time to set up an account on PhotoBucket of some similar site to post them.
To me, it depends what your intentions are for the car. If you want to keep it as a matching numbers resto, then have the 186's redone. They're good heads, even with 1.94" valves. Another option is to put a set of Vortec's on it. They'll probably perform a bit better. But if you do that, then keep all of the original parts to pass along with the car when and if it comes time to sell it.
Vinco has it right, depends on your intentions for the car.
Aftermarket is the way to go on heads if you're after performance. But I'm sure you can make the car plenty quick with just redoing the current heads.
I had a set of old 305 heads that had some work done to them on my engine a while back, and it made decent power, I was happy with it for a long time. Put on some aftermarket vortec heads with a new cam and intake and totally woke the motor up, its a whole different animal now.
Just depends on what you want to do and how much you have to spend I guess.
Hopefully when you pulled the motor you remembered to disconnect your oil pressure line out of the block by the distributor. I forgot that one time, and that copper line had to be replaced after that one, haha!
Aftermarket is the way to go on heads if you're after performance. But I'm sure you can make the car plenty quick with just redoing the current heads.
I had a set of old 305 heads that had some work done to them on my engine a while back, and it made decent power, I was happy with it for a long time. Put on some aftermarket vortec heads with a new cam and intake and totally woke the motor up, its a whole different animal now.
Just depends on what you want to do and how much you have to spend I guess.
Hopefully when you pulled the motor you remembered to disconnect your oil pressure line out of the block by the distributor. I forgot that one time, and that copper line had to be replaced after that one, haha!
That's what I am planning on doing, that is have the 186's redone, and keep them even if I put different heads on.To me, it depends what your intentions are for the car. If you want to keep it as a matching numbers resto, then have the 186's redone. They're good heads, even with 1.94" valves. Another option is to put a set of Vortec's on it. They'll probably perform a bit better. But if you do that, then keep all of the original parts to pass along with the car when and if it comes time to sell it.
I have a set of new Iron Eagles that I will probably bolt on for now.
I am keeping all the OEM parts that I replace with new or aftermarket parts.
I worked on tearing the engine down until l0:30PM.
I drained the water and oil out of it, well most of the water. The water jacket plug on the left side refused to come out, so I had to drill a hole in it to drain it, and will work on getting the rest of the plug out later. It is really stuck in the block. There is no reason to put plugs in that tight. I may even put draincocks in instead of plain plugs.
I set up a dial indicator and degree wheel and checked the duration and lift of the cam. It looks like the cam has .420" - .430" lift on both the intakes and exhausts, with 210 degrees duration on the intakes and 223 degrees duration on the exhausts. That makes it a really mild cam, probably a direct replacement for the stock cam. Some of the lifters are showing funny wear patterns on the cam faces and one has a small groove in the bottom so it must have stuck in the bore at one time and not rotated. It doesn't really matter because I'm going to replace the cam and lifters anyway.
The oil rings must not have been scraping any oil off the walls at all. It was really pumping oil, I never saw one so bad.
Number 2 piston was actually washed clean on the top except for a small area under the spark plug from all the oil in the cylinder. A couple of others were nearly as bad.
There is no detectable wear at all in the cylinders and the honing cross hatching is still visible, so I can just hone them a little to break the glaze and be ready to put new rings in.
Even though the oil rings can't be doing their job, the other rings still have a lot of drag and it turns over pretty hard. It does appear that the compression rings were doing their job, as there is no signs of leakage past the top two rings.
The cylinders are bored .040" oversize, not .030" over like the paperwork says it was, so it is actually 358 cubic inches. I looked up the piston part numbers, they are Speed Pro Hypereutectic pistons and according to the calculator on Summit Racing's site, the compression ratio should be around 10.6 to 1, which is pretty good.
The oil pan was a ***** to get off as who ever put it on used a black silicone instead a regular gasket and it was really tenacious. I had to drive a thin putty knife all the way around between the block and pan to get it off. I thought I was going to bend the crap out of the pan rail before I finally got it off.
Tomorrow night I'll pull the lifters and cam out, and then turn the block over and take the pistons out, and then remove the crankshaft and see what shape it and the bearings are in.
I'm thinking about taking the block into one of the local shops and getting it cleaned after I hone it out. The grit from honing gets into everything, and I want it squeaky clean when I put it back together.
I drained the water and oil out of it, well most of the water. The water jacket plug on the left side refused to come out, so I had to drill a hole in it to drain it, and will work on getting the rest of the plug out later. It is really stuck in the block. There is no reason to put plugs in that tight. I may even put draincocks in instead of plain plugs.
I set up a dial indicator and degree wheel and checked the duration and lift of the cam. It looks like the cam has .420" - .430" lift on both the intakes and exhausts, with 210 degrees duration on the intakes and 223 degrees duration on the exhausts. That makes it a really mild cam, probably a direct replacement for the stock cam. Some of the lifters are showing funny wear patterns on the cam faces and one has a small groove in the bottom so it must have stuck in the bore at one time and not rotated. It doesn't really matter because I'm going to replace the cam and lifters anyway.
The oil rings must not have been scraping any oil off the walls at all. It was really pumping oil, I never saw one so bad.
Number 2 piston was actually washed clean on the top except for a small area under the spark plug from all the oil in the cylinder. A couple of others were nearly as bad.
There is no detectable wear at all in the cylinders and the honing cross hatching is still visible, so I can just hone them a little to break the glaze and be ready to put new rings in.
Even though the oil rings can't be doing their job, the other rings still have a lot of drag and it turns over pretty hard. It does appear that the compression rings were doing their job, as there is no signs of leakage past the top two rings.
The cylinders are bored .040" oversize, not .030" over like the paperwork says it was, so it is actually 358 cubic inches. I looked up the piston part numbers, they are Speed Pro Hypereutectic pistons and according to the calculator on Summit Racing's site, the compression ratio should be around 10.6 to 1, which is pretty good.
The oil pan was a ***** to get off as who ever put it on used a black silicone instead a regular gasket and it was really tenacious. I had to drive a thin putty knife all the way around between the block and pan to get it off. I thought I was going to bend the crap out of the pan rail before I finally got it off.
Tomorrow night I'll pull the lifters and cam out, and then turn the block over and take the pistons out, and then remove the crankshaft and see what shape it and the bearings are in.
I'm thinking about taking the block into one of the local shops and getting it cleaned after I hone it out. The grit from honing gets into everything, and I want it squeaky clean when I put it back together.
I had checked the compression a while back, soon after I got it and it was really good and all the cylinders were within 10 psi. I would have done a leakdown test but my tester is out at my airport hangar, and I didn't feel like a 20 mile drive to get it.Do a compression and leak down test before you do anything to see whats causing the plugs to oil foul. RICK
The oil rings are obviously at fault as the cylinders are being flooded with oil. When I pull the pistons it will be interesting to see if there are any oil rings even installed on the pistons. I've never seen a fresh ring job ( less than 3000 miles) go bad so fast.
I'm curious as to why.
Got the engine torn completely apart last night. I even managed to get the water drain plug out, although who ever put it in tightened it way to tight. Had to drill it out really thin and then heat it up red hot with the torch, let it cool off, and take it out with an easy out. The oil rings look okay and fit the bores properly, but don't have much tension on them. I'm not sure what is going on with them. I am working on chasing out all the threaded holes for the head bolts, oil pan, main bearing caps and front cover with taps so everything goes back together easily. All the bearings looked good also, hardly any wear on them, but you can't use them over so I'll get new ones. Them cam looks really good, so someone could install it with new lifters and it would run a long time. It is a Crane H-260-2 cam, a replacement for the stock cam, was only good for 1500 - 5000 RPM, but has good low end torque.
Tonight I want to finish chasing out the bolt holes, and then give the bores a quick hone job to break the glaze for the new rings. Then it will be ready to take to the shop to be hot tanked so it is nice and clean to put back together. I'm going to try to order the rings, bearings and a few other parts from Summit today so I will have everything I need to put it back together.
Anyone have any suggestions for rings? I see cast iron, ductile iron, moly and plasma coated rings, so there are lots of choices. This is just a street engine, maybe a trip to the track a couples of times.
Tonight I want to finish chasing out the bolt holes, and then give the bores a quick hone job to break the glaze for the new rings. Then it will be ready to take to the shop to be hot tanked so it is nice and clean to put back together. I'm going to try to order the rings, bearings and a few other parts from Summit today so I will have everything I need to put it back together.
Anyone have any suggestions for rings? I see cast iron, ductile iron, moly and plasma coated rings, so there are lots of choices. This is just a street engine, maybe a trip to the track a couples of times.
When it comes back from the machine shop do the bolt holes again :yes:Got the engine torn completely apart last night. I even managed to get the water drain plug out, although who ever put it in tightened it way to tight. Had to drill it out really thin and then heat it up red hot with the torch, let it cool off, and take it out with an easy out. The oil rings look okay and fit the bores properly, but don't have much tension on them. I'm not sure what is going on with them. I am working on chasing out all the threaded holes for the head bolts, oil pan, main bearing caps and front cover with taps so everything goes back together easily. All the bearings looked good also, hardly any wear on them, but you can't use them over so I'll get new ones. Them cam looks really good, so someone could install it with new lifters and it would run a long time. It is a Crane H-260-2 cam, a replacement for the stock cam, was only good for 1500 - 5000 RPM, but has good low end torque.
Tonight I want to finish chasing out the bolt holes, and then give the bores a quick hone job to break the glaze for the new rings. Then it will be ready to take to the shop to be hot tanked so it is nice and clean to put back together. I'm going to try to order the rings, bearings and a few other parts from Summit today so I will have everything I need to put it back together.
Anyone have any suggestions for rings? I see cast iron, ductile iron, moly and plasma coated rings, so there are lots of choices. This is just a street engine, maybe a trip to the track a couples of times.
I will chase out all the holes again when I get it back.When it comes back from the machine shop do the bolt holes again :yes:
Finished chasing out all the holes and cleaning up all the gasket surfaces Friday night. Got out my Aamco cylinder hone and broke the glaze in the cylinders and put in a crosshatch pattern for the new rings. There was virtually no ring wear on the cylinders, maybe .001" or so, was hard to measure with my inside micrometer. I started cleaning up all the parts and pieces and glass bead blasted the tops of the pistons to remove all the caked and baked on oil deposits. All the ring groves are clean as new and there is only a little bit of deposits above the 2nd and top rings to clean up. Whoever put it together slathered red silicone on all the the head bolts, so I am soaking them in mineral spirits to soften it up and make it easy to brush off.
Now I have a dilemma. When I dropped off the 350 block at the shop on Saturday, they had my 400 block finished being clearanced for the 4.00" Eagle stroker crank I bought for it.
Soooo, do I put the 434 together and put it in now, and when I get the 350 back assemble it to be installed if I sell the car or decide to bring it back to stock condition? Or, do I wait for the 350 block and put it back in the car for now, and put the 434 in later?
I would like to put some non-stock items in/on it, like a 6 quart oil pan, windage tray and good oil pump, and maybe even a roller cam and I haven't decided on just which ones I want to use yet.
Throw the 434 in there and have some fun with it, and coat the 350 in cosmoline to preserve it, without putting it together, until you're ready to either show it as a numbers-matching resto or sell it.
4
I finished installing piston/rod assemblies in the 434 block last night (It's 12:30AM now.) and degreed the cam. Cam timing is right on the money, 108 degree intake centerline. Installed front cover and damper, but the Summit billet timing pointer isn't the correct one. It needs to be taller and set out from the front cover further. I installed the stamped one that came with the cover for now. Put oil pump on and dry installed the Moroso pan to see where I am going to have to bump it for rod bolt clearance. I don't think the one piece Felpro 1885 one piece pan gasket is correct either, as it just barely touches the pan in the front at the timing cover. Looks like I need a Felpro 1880 instead.
Trying to decide whether to paint the oil pan or leave it as is.
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Trying to decide whether to paint the oil pan or leave it as is.
If you are using a peformance gasket you may want to look over this link as most performance gaskets require this hole for proper cooling.
http://www.chevyhiperformance.com/techarticles/90678_small_block_400_cooling_tricks/index.html
http://www.chevyhiperformance.com/techarticles/90678_small_block_400_cooling_tricks/index.html
I drilled the new holes as per the diagram and the head gasket.If you are using a peformance gasket you may want to look over this link as most performance gaskets require this hole for proper cooling.
http://www.chevyhiperformance.com/techarticles/90678_small_block_400_cooling_tricks/index.html
Been working on the 434 almost every evening lately and its coming along. As you can see, it's almost all together, I put oil and break-in additive in it and ran the oil pump with a drill until I got oil coming out of all the pushrods and running down on to the valve springs. It held a little over 60 psi.
Didn't get a picture of it, but I set the MSD Atomic Fuel Injection throttle body on it and am checking for clearance for the fitting behind it that supplies vacuum to the brake booster. Unless I can fabricate a really low profile fitting, I am going to have to put a 1/2" spacer under the throttle body to clear the fitting.
The Atomic FI gives you the option of using the advance in the distributor, or locking out the centrifugal advance and letting the FI set the advance electronically. Only problem is that I have an MSD ready to run distributor and it looks like I need the Pro Billet distributor to do the electronic advance. I may call MSD on Tuesday to see if that's the case.
I'm getting excited about getting in back in the car and firing it up.
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Didn't get a picture of it, but I set the MSD Atomic Fuel Injection throttle body on it and am checking for clearance for the fitting behind it that supplies vacuum to the brake booster. Unless I can fabricate a really low profile fitting, I am going to have to put a 1/2" spacer under the throttle body to clear the fitting.
The Atomic FI gives you the option of using the advance in the distributor, or locking out the centrifugal advance and letting the FI set the advance electronically. Only problem is that I have an MSD ready to run distributor and it looks like I need the Pro Billet distributor to do the electronic advance. I may call MSD on Tuesday to see if that's the case.
I'm getting excited about getting in back in the car and firing it up.
The engine looks great, really clean!
IMO I'd change out that Fram oil filter for something else (AC Delco, Wix, Purolator, etc). I noticed my car had lower oil psi with one and several others have had issues in the past as well. I switched to Wix and have had good luck with their filters.
I like those valve covers too! Looks good!
IMO I'd change out that Fram oil filter for something else (AC Delco, Wix, Purolator, etc). I noticed my car had lower oil psi with one and several others have had issues in the past as well. I switched to Wix and have had good luck with their filters.
I like those valve covers too! Looks good!
Thanks.The engine looks great, really clean!
IMO I'd change out that Fram oil filter for something else (AC Delco, Wix, Purolator, etc). I noticed my car had lower oil psi with one and several others have had issues in the past as well. I switched to Wix and have had good luck with their filters.
I like those valve covers too! Looks good!
I have used Fram filters for many years on cars, trucks, lawn equipment and airplanes and have never had any problems. Not sure why a Fram would lower the oil pressure unless it wasn't the proper one for the application.
I debated buying the valve covers for a couple of months, it's just that $200 seems like a lot of money for a pair of die cast and powder coated valve covers.
I picked up a really nice subframe for $150 today at the local Blueberry Festival Car Show and Swap meet. Will only need very minor work to get it ready to blast and paint. Mine has numerous places where chains, hooks and whatever else have bent deformed and torn it over the last 42 years.
Fram don't work on any of my engines with the filter bypass plugged you won't see over 30 pounds of pressure, That being said if the bypass is left in the pressure is fine which means there is a lot of oil being bypassed instead of going through the filter.
WIX or NAPA gold filters seem to work the best for me.
WIX or NAPA gold filters seem to work the best for me.
1 - 20 of 23 Posts
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