FiveCar

Thanks to the help of several key LamboPower board members as well as many discussions with local performance auto mechanics, I'd like to summarize here the things I've learned about doing your own valve adjustment. Typically, this should save you about $2-3k, depending on your dealership. Background (most folks can skip this) Valves control when a cylinder in an engine gets intake (air/gas) and releases exhaust. In Lambos, valves are opened and closed mechanically by four rotating camshafts, each of which has tappets (egg-shaped bumps) that press against spacers sitting in buckets on top of the valve. So a valve opens when a tappet on a camshaft rotates to where it pushes against a spacer, which pushes against the bucket it sits in, which pushes a valve down into the cylinder. Over time, these mechanisms wear and distort such that the gap ("lash" or "clearance") between a tappet and its spacer changes from the factory spec. When this happens, valves begin to open/close too soon or too late, resulting in lost efficiency (at best) and burned valves (at worst -- or perhaps even worse can happen, I suppose). Lambo recommends adjusting your valves every 15k miles. Intro You can adjust your valves without removing the engine. It's a lot easier with the engine out, but it's definitely doable with the engine in. For your first time, a valve adjustment will likely take between 5-8 hours, depending on how mechanically inclined you are and also how carefully you do your work. Overall, the job isn't difficult. The overall approach is simple: Remove the valve covers Measure existing clearances Measure existing spacers Do some simple subtraction to figure out what spacers you need Install new spacers Close everything up and drive away None of it is difficult, though it can be time-consuming. You'd be amazed at how easy it is. Materials You'll mostly be working with simple hand tools that can be obtained from anywhere. Metric sockets. Most popularly, the 10mm, 13mm, and one 24mm for turning the engine. Socket extension bar, perhaps 12" long. Breaker bar for turning the engine. A set of metric tappet feeler gauges (about $5). Paper, pencil, and perhaps a little tape to mark stuff A valve adjustment tool. You could spend $220 and buy one. You could rent one for $22/wk. Or you could make one for $4 like I described here. A nifty Valve Adjustment Guide, which I created and provide here: Diablo_Valve_Adjustment.pdf (Optional) A spreadsheet to help double-check your math, which I've hosted on Google Docs here. Removing the Intake Manifold This part might be fairly obvious, so I'll be brief. You'll want to lift off the entire intake manifold by unplugging everything from it and taking it off the engine. Detach the intake hoses that come from the air filter; detach fuel lines; unhook electricals (I'd recommend marking them unless you've got a great memory); unscrew the throttle linkage. Lift it off the engine with a friend -- it's not heavy, but it's a bit bulky, especially if your engine is still in the car. More details here. Remove the Valve Covers I've also described this in a previous thread, so please see more details there. Measure Clearances Use a set of metric tappet feeler gauges to measure the clearances between your tappets and the spacer disks below them. Do this when the engine is cold (that's important -- things expand and change when the engine heats up). Use tappet feeler gauges, not regular flat feeler gauges. Tappet feeler gauges have a bend in them that make them easier to slide under the tappets. The right measurement is where the gauge slips in without much force and glides around, but clearly contacts both the tappet and the spacer snugly. You should measure the gaps only when tappets are facing up so that they are at their maximum gap with the spacer below. You'll be working on a pair of tappets and spacers at a time, cranking the engine once in a while to expose new pairs of tappets to work on. Record the gaps, perhaps in the Valve Adjustment Guide I've uploaded above. Next, remove the spacers under the tappets you've just measured by inserting a valve adjustment tool (described above and in this other post) between the pair of spacers. Measure and record the thickness of each spacer by using digital calipers. You could alternatively rely on the spacer's label ("3-80" means 3.8mm), but that requires some faith that the spacer hasn't itself worn down through heavy use. You need to measure the spacers' thickness so that you can derive what thickness of spacer you need in order to achieve the ideal clearance. Once you've done all the pairs of tappets that are facing up, you'll need to turn the engine a bit in order to get other pairs of tappets in the correct position. You can either turn the engine from the flywheel side by using the $600 Lambo tool, or alternatively use a 24mm socket on the crankshaft bolt, pictured below. Note that you should only ever turn the flywheel clockwise, or the crankshaft bolt counterclockwise. This is very important. Seriously -- you could mess up your timings. Double-check yourself before turning anything. And loosen your spark plugs, if you haven't taken the opportunity to replace them. This will allow air to enter the cylinders when you turn the engine and greatly simplify the job. And be in neutral. Using a breaker bar and and a 24mm socket, you should be able to easily turn the engine. Work on new pairs of tappets until you've measured all clearances and all spacer thicknesses. Getting New Spacers You can do some simple math to figure out the new spacers you need, or alternatively use the spreadsheet I uploaded above (in the Materials section) to help double-check your math. The spacers are 29mm wide, which is a size that almost nobody local will carry (but do let me know if you find compatible ones). Lambo will sell you most spacers for $6-8 each. But -- and here's the reason you've gotta love 'em -- every once in a while, a spacer will be $40. Like 3.70mm. Why, you ask? Because those are the most popular spacers. Nothing like a little blatant gouging to show some love for its customers. You can also get a local machine shop to use a surface grinder to reduce a thicker spacer to a thinner one. This will take an expert machinist perhaps 5 minutes a piece to do a really careful job. And you want a careful job -- you do NOT want spacers that are crooked. I ended up buying most of my spacers, and getting a machinist at a performance auto shop with 30 years of experience to do the 3.70mm ones. He did a great job. Insert Spacers Replace the right spacers with new ones you've gotten by using the valve adjustment tool to lower the buckets and then setting each spacer firmly in its bucket. I'd recommend setting the spacers with their label-side down so that you'll have some idea what you put in when you do your next valve adjustment. Check your clearances to make sure you've done a good job. Congratulate yourself. Drive Away You'll need to put the valve covers back on (with new gaskets), tighten your spark plugs, and install the intake manifold (using new gaskets as well -- I'd recommend Viton ones). If you have specific questions, or suggestions of things to add to this guide, please let me know and I'll edit this post to incorporate your contributions! Thanks, everyone, for your help and support.

Doing a valve adjustment on a Diablo turns out to be pretty easy -- I'll post another thread on that. In the meantime, one of the trickiest parts is how to remove the spacer shims in order to install different shims. Lambo will sell you a special tool (part number 961195014, more than $200 USD) like the one below: Others will tell you to do things like remove the cams. I started going down that path, but didn't want to deal with the possibility of mismanaging the timing when reinstalling the chain, or changing the chain tension, etc. I considered getting a local machine shop to make me a tool, but they quoted some pretty high prices (at $95/hr), so I instead made my own valve adjustment tool. Total Cost: $3.99 + sales tax (assuming you own a bench grinder -- I didn't, so my cost was actually $48 total). Estimated Time: 20 minutes, ignoring travel time to your nearest Harbor Freight Materials: 5-1/2" Brake Spoon (Harbor Freight part number 96961) 6" or 8" bench grinder. I got a Ryobi from Home Depot for $45 Leather gloves Metric ruler with millimeter markings Instructions: Unpack brake spoon Wear gloves and goggles. The goggles are an option play, depending on your penchant for blindness, but the gloves are a requirement unless you've lost all sense of temperature in your hands. Things are about to get hot. Grind down the sides of the last two inches of the spoon so that it becomes 7mm wide. Use the rough wheel on the grinder. Don't just grind one side to get down to 7mm -- grind both. This way, you get a nice square base instead of a rounded base on one side. This step should take no more than 2-3 minutes. Taper the tip of the spoon by grinding the underside so that the tip is around 1mm thick, and the thickest part at the curve is 5mm. Precision here isn't too important. What's important is that the taper remains reasonably smooth, so that the tool is easy to use. Test your handiwork by inserting spoon between the cam and two valve buckets. Everything should work just fine. Buy yourself and a few buddies a round of drinks with the money you saved. The most important step of this is that the spoon be 7mm wide. Any wider, and you won't fit between the spacers. Any narrower, and you'll keep popping one or the other bucket. 7mm. Happy trails.

I ended up buying a new Kevlar clutch from Hi Tech Exotics. Photos below. You'll note that almost any new clutch will look great next to the original worn ones. Hi Tech essentially buys a new OEM balanced clutch kit and then refinishes it with Kevlar and rebalances it. Don't be fooled by the shipping: the Lambo crate looks great and all, but the materials were packed so poorly inside that the pressure plate and the flywheel came apart from one another (they weren't screwed together at all) and ended up scratching each other. Fortunately, the damage seemed mostly cosmetic. But one would expect when buying something for several thousand dollars that the sellers would invest, say, $0.50 in a few screws to keep things together. In fairness to the seller, he claimed that they used to secure the whole assembly with screws, but that the screws would get bent and damaged during shipping. Hmmm. Regardless of what you think of that claim, they were decent enough to refund me $100 for the damage. I will report back on how the Kevlar clutch feels once I actually drive this thing. I'd also like to do a comparison with a ClutchMaster-finished Kevlar clutch -- if any of you have that, and live near Seattle, PM me.

I've added some photos of the Viton seals, in case it helps. The top-left one is the original oil seal that I removed from the exit shaft of the transmission; the one under it is the new seal. Note that all of these are Viton seals and gaskets, which means they'll be far more heat resistant. If you remove a seal from your engine and it seems to have hardened or melted a little, put a Viton seal in and it'll do much better. They can take almost double the heat of the regular black rubber gaskets. @RHershey -- I'm not sure the part number and brand actually matter, though I've enclosed the original packaging for you in case it helps. The most important things are: 36mm x 52mm x 7mm, and Viton. Most industrial oil seal shops will be able to source you the right seal, and Viton's something like DuPont product so it'll all be about 4x as much as regular seals. However, compared with the parts from Lambo direct, even Viton seals are considered a steal.

Thanks for taking a look, @RHennessey. Let me know what you find. For parts diagrams, I believe the official party line is that you should own a parts manual. I don't actually own one. Instead, I use a Lambo parts site (which apparently I can't name on here because they might not be a sponsor); it rhymes with BremboStuff.com.

Ok, I took my fuel hose off last night but decided not to trim it because I don't think it'll help in my situation. The side of the hose nearer to the fuel door fits over a sleeve that's so long that the only flexible portion is about an inch or two between it and the gas tank -- I think that relatively short distance is the real problem. Trimming the hose won't allow it to bend any less, at least in my case. Part #36 below is essentially too long. For those of you who trimmed your fuel hoses, was #36 much shorter? Mine seems to be around 4", which leaves it only an inch or two away from the top entry of the fuel tank.

Since I had the engine out, I decided to go ahead and do a valve adjustment ahead of the 30k schedule (only by a few hundred miles). First, you need to remove the intake manifold after unplugging the 8-9 wires that connect to parts below it. The only tricky one to look out for is a rubber hose attached to the interior of the manifold. I've circled its location below. Once the few wires and hoses are detached, unscrew the three nuts that run down the center of the manifold and lift the manifold up to remove it. It's not heavy at all, so this entire job is easily doable by one person. Next, unscrew the end caps on the two sides of each header. The ones with the thick gasket are a bit tougher to get out, but take your time and gently pry them from all four corners until they come off. Unplug all spark plug wires. Unscrew the huge sockets that form the tunnel for each spark plug. Undo the five nuts on the top of each cover. Carefully lift the covers off. Note that when you're done, you'll need to replace all the gaskets. I'd recommend upgrading to Viton gaskets, which tend to handle heat a lot better than standard black rubber gaskets. You'll be able to buy Viton gaskets for the same price as Lambo's standard gaskets by going to any decent industrial gasket supplier. I'll post updates on the actual valve adjustment over the next few days.

Ok, removed it successfully with advice from @jefflambo. It's really easy. All you have to do is gently wedge something into each corner and ease the cap off. It took a lot more working than the flat caps, but in the end it all came off with no problems. Thanks, everyone.

Two things about this: I find holding the handle at about 7-8 o'clock as the best angle. This is in a system where holding the handle "normally" would be 6 o'clock, and 9 o'clock points directly to the rear of the vehicle. That said, I've heard of at least one Lambo owner claiming that cutting the fuel pipe (between the lid and the tank) by a quarter inch (0.25", as improbable as that seems) eliminates the problem entirely. It has to do with the vapor pressure, I believe. Since I have the engine out, I'm going to trim my fuel pipe and report back on the results. In the meantime, I hope 7 to 8 o'clock helps.

How do you remove the camshaft cover plate highlighted below (#24)? I've gotten everything else off, and am ready to remove the cover, but I can't seem to figure out how to remove this thing and I don't want to use force. After removing the four main nuts on it (#28), I gently pried from the side (#24) but it wouldn't come off. Do you have to remove #43 in order to reach an inner screw? Or the solenoid valve that goes into the base of the plate near #43? I unscrewed the solenoid valve, but didn't want to pull on it hard in case something is attached. Thanks for the tips. I'll post photos when I'm done.

The oil seal on the driveshaft is 36mm x 52mm x 7mm (ID, OD, thickness). SKF 562965 is that exact size... however, 562965 is not high-temperature ("Viton"), so it tops out at something over 100 degrees Celcius. Note that the OEM part is Viton, which takes you up to around 315 degrees C. A local industrial seal vendor suggested that I stay with Viton, which is usually brown instead of black rubber. Note that the same seals using Viton cost around $20, whereas a non-Viton seal is indeed around $4. I went with a Viton seal, and will install it this weekend. Thanks again to @limey for giving the SKF number, which helped me get the exact dimensions needed! I just wanted to highlight that you might want to go with a Viton-based seal of the same measurements in order to be absolutely certain that the seal won't degrade fast at higher temps.

@Jeff -- having trouble finding that part on websites. Do you know where I could get the part? @AKA cartman -- I'll post photos and more details after I receive it. Right now, the seller's not exactly on my high-trust list, given that he told me he sells around 50 of those units a year. A bit hard for me to believe, when total Diablo production numbers were around 200 a year. But we'll see.

Ended up deciding to buy a brand new kevlar clutch from Hi Tech Exotics. I'll install and keep you guys posted on how it goes.

Looks like a new starter motor runs $1,400 USD, which is way more than I'd want to pay just to replace it. Are there any alternatives? I didn't see any listed in the sticky parts thread...

I've heard many people say that the starter motor should be replaced, but when I talked with a Lambo tech, he said he basically never sees failed starters. Is it a common problem? I do plan to adjust the valves, and may replace the head gaskets if I see any seepage. I'm currently trying to decide whether to go with a ClutchMasters resurfaced clutch or with a Hi Tech Exotics kevlar setup. I suppose I could go with the stock clutch, but I don't want it to fail again in a year. Let me know if you've used ClutchMasters or Hi Tech before -- I've heard varying opinions on the relative benefits of each. Thanks, everyone! Oh -- and if there are specific photos you'd like me to take while the engine is out, let me know.

I've removed the transmission and detached the pressure plate and clutch. Looks like it might all need to be resurfaced by ClutchMasters. One thing that I'm not sure about is the clutch itself seems to have a crack in it on one side of the material (not the thin metal disk, but the coating/lining that's on both surfaces of the metal; one side of that lining has a crack that goes from the outer edge to the inner edge). Does that disk need to be replaced completely, or can it be resurfaced? Transmission removal was a fairly easy one-man job, using a hoist to balance the weight. I bet reassembly will take two people.

So this weekend, using the engine hoist and braces that huntnphool so generously loaned me, I lifted the engine out. Overall, the job was a lot easier than I thought it'd be. None of it was difficult. I took a lot longer than some folks because I wanted to be extra careful all the way, so I labeled everything as I went. I estimate the whole job took me about 20 hours, working leisurely, and the hoisting itself took about an hour. Photos below. Next, it's time to check out the clutch. I then took the transmission off. Good times, good times.

Thanks, Jeff. You were absolutely right -- engine came out with no problems, with that bar in place.

Ok, I made a second attempt at this o-ring and removed it in less than 5 minutes. It was a lot easier this time. Basically started it off with the snap-ring pliers, just enough for one edge to clear the metal that it was against, then gently lifted from that edge all the way around to the other side with a flathead screwdriver. Very little effort. The clutch slave cylinder is now safely out of the way, with its hose still attached, so I won't need to bleed it afterwards. The only thing left before lifting the engine out tomorrow is the anti-roll bar! Thanks, everyone.

I've been told by a Lambo tech that you can remove the clutch slave cylinder without having the bleed the hose by detaching the entire cylinder from the bell housing by removing the o-ring (pictured below). I've tried to use a snap ring remover, and was able to open the ring up a little and get one end of it to clear the ridge that it was holding. However, the snap ring remover keeps coming off of the ring itself, making it hard to clear both ends of the ridge and to bring the whole ring out. What's the best way to remove this ring? And, in your opinion, is it really easier than removing the hose and bleeding/filling the cylinder later? (I've bled and filled it once, when replacing my clutch rod -- it wasn't hard, but it was messy; this whole slave-cylinder-removal-with-a-single-ring approach had sounded easier).

Before pulling out the engine, is removing the anti-roll bar necessary? I've circled it below. I see it completely attached in the pre- and post-engine removal photos from the instructions here (figures 19 and 21): http://www.lamboweb.com/Repairs_Section/Di...ving_Engine.htm. So it must be possible without removing the anti-roll bar. However, it seems like the engine would need a lot less tilt if I removed the bar. I've already removed all screws from it, including the ones attaching it to the suspension, so that the bar is free-floating. I've also removed both wheel well covers to give it more clearance. However, the bar still won't slide out, trapped between the suspension spring on one side and the radiator input air duct on the other. Does removing it make it easier to get the engine out? If so, what's the best way to remove it? Thanks.

Thanks, @limey. Awesome tips, as usual. Yes, disconnected the shifter housing wires (purple and green), along with the reverse-detection wire I had installed for my reverse camera. Also saw the sneaky speedo transducer, but didn't realize there's a ground wire for the tranny -- I'll look again for that. Thanks for mentioning it! I'm either replacing the clutch, or resurfacing it with ClutchMasters. I'm also planning to look for anything else that I can easily fix while I'm in there. @ExoticCarSearch: I do indeed have a shop manual, though it's funny how few directions it has compared to, say, a Honda shop manual (which would list exact torques for all bolts and also show pretty awesome diagrams). The entire SV shop manual has a column on one page talking about engine removal -- less than about 1000 words, and the only picture is of a guy with a paunch doing the impossible (taking the engine out with the entire exhaust, including cats and mufflers, attached). Good times, good times. My head gaskets show very slight leakage, almost undetectable. How important is it to do the valve adjustment? I might go ahead and get that done, though from what I understand, it requires several specialized tools. Definitely going to check out the flywheel teeth/etc. Thanks again for the great advice, everyone.

Ok -- update: both the throttle cable and the thick engine wiring removed successfully. The thick wiring didn't disconnect as easily because the silver ring had gotten separated from the underlying black plastic; with @limey's suggestion, I gave it another try and it came right apart. Every wire and hose is now disconnected. I'll be lifting it out this weekend. Any final tips on tilting the engine out? I believe I need to lift the car a little bit in order to give the tranny enough clearance -- does that sound right? Thanks again for all the help. This project has actually turned out a lot easier than I expected. About 8 hours in so far, and already prepped to hoist the engine.

Sure thing. Previously did a timing belt on an Accord, which required removing the engine mount and a bunch of other stuff. Also talked multiple times with a Lambo tech, as well as a board member that has done it before. Are you worried?

@limey -- thanks for the throttle linkage tip. I did unscrew the silver part of the big cable, but it doesn't pull apart (easily). In fact, it's not clear at all what the silver part was holding together -- the black plastic appears to be fused together on both sides. Do I need to unscrew the four little black screws? The inside of the cable has a ton of little wires, so I want to be careful not to randomly pull on it too hard... The silver thing unscrews, but seems unattached to the black plastic shielding -- it essentially moves freely down the cable once you unscrew it. Is there something else I need to do? thanks again.