I have a b18c5 which burns alot of oil under vtec as in blue smoke cloud and drinks oils quick if you hit it hard in vtec alot. I did a compression test on the car and it has low compression on the cylinder #1 if i recall around 115 and the other 3 were around 165-170. Just wondering what would be my best and cheapest (with in reasons ) on a rebuild ? Looks like i will need to do the rings and valve guides on this if not more. I am looking for basically a stock rebuild. What kit aftermarket or oem would i use? if i am going just oem stock rebuild is there anything i should upgrade (Dont care about performance) more of a reliability upgrade. Thanks!

 

OEM Honda 81.25mm pistons, rings, and wrist pins for the B18C5. Punch it out the extra .25mm to remove any taper from the cylinder walls. ARP rod bolts, OEM Honda con rod and crankshaft bearings. OEM Honda gaskets. ARP Head studs. OEM Honda or Ferrea valve guides. In short, OEM Honda for everything other than the ARP rod bolts and head studs. Best and cheap don't go well in the same sentence. What is your realistic budget for this rebuild including the cost of machine work? That will help myself and other members make recommendations on parts.

 

i would say 1000-1500. I can get honda parts at cost because my cousin works there. Why would i need to replace pistons? i wouldnt be able to reuse piston and con rod?

 

It really depends on how the bottom end looks. If the bottom end still looks good, ie no scratches or grooves, you maybe able to get away with just changing valve seals (the guides don't leak, the seals do). However, given your compression numbers either you have a bad head gasket or the cylinder walls are tore up. Pull the head and check. You can replace the valve seals while you have the head off.

Regarding 1998GsRIntegra comment of new pistons, if your cylinder walls are scored or groves, you'll need to bore it out anyways. If you bore, you have to get bigger pistons. You could just hone it if the walls aren't bad but that won't remove any taper or out of roundness. You can check for that if you have the right tools.

ARP head studs are nice, rod bolts I think are overkill on a stock build unless your rods are out of round. You'll have to resize them if that is the case so you can replace the bolts at that time.

Again, it is really going to come down to what everything looks like as you start to take it apart. You also may want to run a leak down test to see if your valves are sealing/seated correctly. If not, you'll need a valve job as well. You should also have the head and block decked at the same time to ensure it is totally flat.

Craig - Who is going through all this right now: http://forums.itrexpo.com/zerothread?id=15399

 

Well, good luck with that. I see you completely missed the sentence directly after the mention of 81.25mm pistons stating why it would be a good idea to use them over the stock 81mm bore pistons.

Craig, you're more or less correct. However, his piston rings are toast. The combination of blue smoke under hard acceleration and the low compression test numbers are a dead give away(in my opinion of course). If valve guides and seals were his sole problem he would experience smoke under mid to high rpm closed throttle situations, not WOT situations. WOT = no manifold vacuum so it is unlikely that a noteworthy amount of oil will get past the valve seals. Under closed throttle at mid to high rpm the manifold is under max vacuum and that is where you will see oil being pulled past the valve seals through the worn out valve guides and burned. Here's the issue you run into. Most of the valve guides on these higher mileage engines are worn out. Most DIY guys do not have the proper tools to measure them so they ignore them and assume the seals are the sole culprit for their car smoking under decel. Now, the valve guide is what centers the valve on the seat as it closes. If you get a nice serdi valve job or what ever, but don't replace the guides, in about 5000 to 10000 miles your valves will hammer the **** out of your valve seats because they are seating unevenly when they close because the guides are worn out and then cease to seal. The other thing you run into is that serdi and neway machines(which most all shops use for valve jobs now because of their convenience), center their cutter head on the guide and cut all three angles at once. Problem is that if your guides aren't straight the cutter will cut the seat unevenly so your valve ends up trying to seat on a lopsided surface.

On another point, most of these engines that are pulled apart for rebuilds have between 12 and 18 thou of taper from top to bottom. That is too much for new honda rings to deal with when they have to seat in. Not to mention the fact that your p2w and ring end gaps are changing dynamically as the piston moves up and down in the bore. So you end up with 12 to 15 thou p2w at the bottom of the bore on a standard 81mm cast piston, but 30 thou on the load axis at the top of the bore, which is way too much for a non forged piston. What that leads to is poor ring seal and oil burning under load.

Rod bolts take a ton of abuse and if you're rebuilding the engine, replace them. When you replace them the rods need to be resized so might as well use arp's. They cost about the same as new con rod bolts from honda and are stronger.

All that said, could you re-ring it, hone the cylinders, change the valve seals, put in new bearings and run it? Yes, and it will burn less oil than when you started, but it won't be any where near perfect. There is a cheap way that will get you back on the road and there is a by the book correct way to rebuild one of these and for that matter any engine. You just have to decide which you want to go with. Do you want something that will be reliable and easily last over 100k miles or are you content with something that will tolerably last 30k miles because you don't plan on keeping it that long anyway?

 

Great advice.

Craig - who went with a bore due to out of round.