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Hi!
I’ll try to be as specific as possible.
Got a 1986-model Volvo 740 Turbo Intercooler. Engine type is B230ET (2.3 liter turbocharged, electronic (Motronic 1.0) fuel injection) and transmission M46 (4-speed manual with overdrive). This car were sold in Norway new, not imported. Since it is older than 1989, it does not have a catalytic converter. Bought it in 2012. This is a car I care very much for and do the best I can to maintain. I also always fill it with 98 octane fuel (93 or so in the US), as specified in the manual. When driving, I never go past 3000 RPM, or use the turbocharger, before it is at full operating temperature.
The engine was at a full rebuild/overhaul for 1,5 years ago, or about 20.000km/12.000 miles ago. This was done at a professional engine workshop. The exact milage before the rebuild is unknown. The speedometer have been manipulated at some point. It did read approximately 220.000km (136.000 miles), but paperwork from the official vehicle authorities suggest it in reality is twice the milage. The engine did have poor compression in one sylinder and several leaks. Thought it was time to get it rebuilt. After I got the car back, I had a tapping sound coming from the engine. I filmed it to capture the sound when I start the car, see link below. You can hear it really well before I open the hood. It does follow the RPM.
I were told it is harmless and just the valves that needed adjustment. I were recommended to not do the adjustment right after the engine rebuild as the parts were seating. Doing it early I would just end up with the same sound again because the parts would not be fully seated. The valves in this engine apparently is of a special type that only the dealership can adjust. I’ve done it twice since the rebuild, but still have the same tapping sounds. It was not like that before the engine rebuild. I am concerned about this noise. No one seems to really care about looking into it or fix it. I’ve been to several workshops, but every time it is either the valves, just harmless/normal or simply “it is an old car, after all”.
I’ve been very precise with the oil changes. I change the oil every 10.000km or 6 months, whichever comes first. The user manual says the same thing too. I always use OEM oil filters. After I got the car back from the rebuild I were told to change the oil after 500km, then 1500km after that, which I did. After that I’ve changed the oil as specified in the manual. I’ve used the exact same oil that the rebuild workshop used and recommend, Castrol Magnatec C3 5W-40 (synthetic). I always check the level once a week, and it has been consistent. Never had to top it up. The manual doesn’t state a specific type of oil, it just shows a chart with different oil types. You can see it in the picture below.
Is this something I should be concerned about? Any suggestions to what this is? If it is the valves, can this be fixed with regular tools in my own garage? At this point I don’t really trust the workshops that say that they cannot adjust the valves because they’re special…
http://www.youtube.com/watch?v=RjIHGwojPkk
[URL=http://s1218.photobucket.com/user/frankbilder/media/olje_zps2axkmpkh.jpg.html][IMG]http://i1218.photobucket.com/albums/dd414/frankbilder/olje_zps2axkmpkh.jpg[/IMG][/URL]
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Not sure of your climate where you live, It looks like 10w-30 would be the oil for the vehicle.
I don’t recommend you doing the valve adjustment. If done wrong you will hurt the motor. did
you get a warranty with the engine rebuilder? Does sound loud.The climate is fairly mild. Rarely goes below -10C in the winter and rarely above +20C in the summer. Not exactly siberia. I were told it is still acceptable to use the oil. Judging from the chart, is does look like it is acceptable. The reason the oil were used, according to the workshop, is because it is better suited for a turbocharged engine.
Did some research regarding valve adjustment, and get the impression the different workshops is right after all. At least very expensive to buy the needed equipment and require some knowledge and skill within valve adjustment. From what I found out, I would need a full set of different feeler gauges. Can’t use regular ones either as it could give wrong measurements. Need some that are called offset feeler gauges. Also need (or at least highly recommended) a special tool to help release the valve shims, as well as an expensive shim set. Well, the valve adjustment at the dealership is like $200, so not exactly cheap either. Though, I do suspect they don’t know what they’re doing since I’ve done it twice within a year and the noise is the same. I can be quite handy when working on the car, but have neither the skill or equipment needed to do the adjustment my self.
The tapping sound is quite loud. You can hear it without problems inside the car and outside it. Someone told me once it did sound like a two cylinder diesel engine.
There should be a warranty on the rebuild. I recently got the water pump replaced on warranty as it failed. I’m at least covered by laws regarding the purchase of services. I’ll contact them again before I start involving the Consumer Council. I just get the impression no one really wants to look at it unless I can provide proof something is wrong. I just wanted to make sure I’m not crazy here and get confirmation that something is out of order with my engine.
I’ve rebuilt the b230 ft in my 1987 Volvo 740. There are ruber absorbers under the lifters that don’t last very long. Once they wear out,(5000 mi) you have to adjust the valves. The valves are adjustable, the shims to go on top of the buckets can be purchased individually from fcp Euro so you don’t need a $250 USD kit of shims.
Unfortunately, you need to have the camshaft removed to do this.
Or buy special tools. Even then without the rubber absorbers it will stay loud. And they only last about one oil change. Get the valves adjusted once, then just ignore the noise. It’s not going to go away.
You can check the valve clearance with regular feeler gauges. It’s easy to do, and must feeler gauges are more than flexible enough. If something is way off, you’ll know because a larger feeler gauge will fit between the cam and the lifter.
The specs are:
0.30mm to 0.40mm cold
0.35mm to 0.45mm hot
When adjusting set to 0.35-0.40 mm cold.Your best bet for preliminary diagnosis would be to narrow down where the noise is coming from. At least to rule out a serious issue. What Timothy S says sounds plausible as to the reason for the noise, but I know literally nothing specific to those cars. But you should be able to check the valve clearances as easily as he suggested. A simple set of feeler gauges and knowing the spec is about all you need. Referencing any valve adjustment video will show you how to check the clearances.
I see. The sound is anyway louder than it should be. It wasn’t like this before the rebuild. I wouldn’t even bought the car if I heard something like that. I’ve been to a couple of Volvo car meetings and listened to other peoples engines and can say none sounded like mine. Even the older B20 engines with pushrods were a lot more quiet.
I’ve used a stethoscope and listened around the engine block. The sound is originating from the top of the engine. I could buy a set of feeler gauges that are what the spec should be and at least measure if something is too loose or tight. Since the gasket is fairly new, it shouldn’t be a problem to reuse it?
I would like to try and avoid buying parts from abroad. Anything above $30 or so (including shipping) is taxed with 25% VAT + handling fees.
Hopefully this is a simple case of incorrect valve clearance.
You said this noise began after the engine was rebuilt. It’s possible that the assembler didn’t pre-lube the camshaft before firing things up for the first time, or didn’t do a proper “break in” procedure, and ended up damaging the cam lobes themselves.
Hopefully everything was done correctly. I’ve at least done exactly as I were told to do during the break-in. Changed the oil (and filter) when I were supposed to. The driving instructions were a little bit vague, though. Were told to drive normally. Not sure what normal is, but my driving style is not to go past 3000 RPM during the first 10 minutes, or reached operating temperature. I didn’t push in the throttle enough to get positive pressure from the turbo either during that period. During the break-in I didn’t really drive with boost in general as I didn’t want to put unnecessary stress on the different components. I drove long trips every day, so it was at operating temperature the whole time. No short distance (and cold engine) trips.
Not sure if this can be related, but I found it a bit odd that almost every oil seal on the engine were leaking (or sweating) a little bit too. I were told that they haven’t seated in properly because they were brand new and should give it some time. After a year the oil stopped sweating around the different places. So guess the workshop was right about that. The oil level would decrease, but never enough for for it to be necessary to top it up inbetween oil changes. Now after the sweating stopped, it doesn’t decrease at all. I can’t see any oil droplets on the ground or hanging from the engine anymore. Probably should give it a good clean. I need to apply new paint several places too as it is flaking off because of the general engine heat.
Thought I’d update this thread. I’ve had my car at the dealership and burned off around 240 USD on valve adjustment. The result wasn’t what I were hoping for. The noise is still there… I then drove to the workshop that did the engine disassembly/install and had them look at my car last week. They confirmed the noise and said it sounded like it came from deeper inside the engine. They had contacted the workshop that did the rebuild and informed them about the sound.
I were told to contact the engine rebuild shop directly, which I did. The guy I spoke with said I should not drive the car and wait for him to check it out. Now comes the bad news, at least for me. He can’t look at the engine until around the middle of August since he is going on vacation now. He did however ask me to change the oil to 10W-40 semi-synthetic, since fully synthetic oils apparently are too thin eventhough they’re the correct viscosity. If the noise went away, I could continue to drive the car. I’ve now changed the oil to what he recommended, but the tapping/knocking sound persists. I were also told to smell and feel the oil I removed, and collect a sample for him to look at. For me it smells like engine oil and it has that slippery feel to it.
Since I can’t be without the car for a month, would it really be dangerous to continue driving it until he gets back from vacation? It has been like this for 1,5 years now already…
I feel like punching babies every time someone suggests using thicker oil to cure an engine noise. It often causes more problems than it solves. Wear is greatly increased during cold start up with thicker oils as it takes them longer to propagate through the engine.
The noise is caused by excessive clearance somewhere. Likely something that was missed during assembly. Engine assembly is a time consuming process that takes care and patients. It’s easy to miss some small detail that can cause a problem like yours. In fact, it’s the reason I always recommend replacement over rebuilding for most people.
That said, it does sound like some clearance is excessive. What clearance I can’t say. You say you already had the valves adjusted so it’s not likely to have anything to do with that. Really you’re at the mercy of the builder to get in there and figure out what the issue is. Sounds like you’ll be waiting till August for that unfortunately. In the mean time,
http://www.ericthecarguy.com/faq/diagnosing-noises-in-your-car
Good luck and please keep us updated.
Yes, I were a bit surprised about the oil. The guy at the shop explained that these older engines have larger clearance between parts in general, which makes fully synthetic oils not recommended. He did a listen to my video and concluded that it isn’t anything critical with how it sounds, so I could continue to drive my car while waiting. He said it shouldn’t sound like that, but it were only annoying and not harmful.
I am a bit unsure how much I can demand. My experience is that I am now considered an expense from the shops perspective. Would it be too much to ask for the engine to be taken out and completely checked? I paid a lot of money for this rebuild, after all.
I would’ve done a replacement, but taking into consideration how rare this engine is and the risk of replacing junk with junk, I opted for rebuild instead. I could have put in a different engine, but the strict vehicle regulations we have here can make it very challenging. A legal engine swap involves written requests to the authorities, documentation, time and money.
At least I have done what I can do on my own.
I’ve been in contact with the engine workshop now. I drove to them and they listened more thoroughly on my engine. They concluded that a shaft going to the oil pump assembly is the culprit. The slot it fits into gets worn and it will rattle around. I just got a bunch of disclaimers, so basically they wouldn’t take any responsibility for this since they just put back what they took out… They said it is really easy to replace, I just had to pull out the flame arrestor/crank case breather and pull out the shaft from the hole.
Now comes the not so fun part… The engine workshop insisted that I could buy this part at Volvo, but it turns out it is discontinued. Now is the big question, what to do now? I’m going to ask around and see if it is possible to machine and “rebuild” this part. If not, I guess I’ll have to kiss a frog and buy a second hand one and most likely end up with the same result. Not uncommon these engines have run at least 400.000 km, or about 250.000 miles, which is the estimated milage of my engine when it was rebuilt.
Guess I’m not so lucky with cars. 😛
The culprit is part number 15, which the arrow points at.
To be honest, I get the impression that those guys are feeding you a poop sandwich.
The only way to confirm that this shaft is your problem, you’d have to remove it and visually inspect both the male and female side of the coupling. If excess clearance does exist, and things are flopping around enough to cause knocking, you’d also be getting irregular spark timing. That shaft drives your distributor.
I don’t see how it can drive the distributor. Perhaps you’re thinking of the older engines that have it in the front? My engine have the distributor on the back on the cam shaft.
Anyhow, I do see your point. All they did were to listen around with a stethoscope. I did pay a small fortune for the rebuild and did request that I wanted it as good as when it left the factory. Doubt it had knocking sounds when it were new.
Perhaps I should pull out the shaft and inspect it. I guess any wear would be rather obvious to spot, even if I don’t have experience.
Spoke with someone else today. That person said this sounds very much like I have something called “piston slap”. Since the noise is best heard when cold, and almost gone when at operating temperature. Can’t really be that oil pump shaft that has gone bad, since it isn’t really a part that is exposed to high wear. It would also need excessive unrealistic wear to, if at all, cause such noises. I’ve even looked at a couple disassembled shafts from engines that have run around 400.000km (250.000 miles). Wasn’t really any wear at all on those. I used some calipers to inspect and found the slotted end to still be flat, no uneven wear.
If it is “piston slap”, then the workshop have messed up big time, since the pistons are too small for the bore used. I were told the only way to fix this 100% is to change pistons and new bore again. Really hope it isn’t that serious…. Either way, that person also suggested the engine should be disassembled and checked. Just listening to the engine with a stethoscope isn’t enough to conclude what’s wrong.
Just to top it off, one of the core plugs popped out the other day… Not sure if it is related, but I’ve had issues with the cooling system too after the rebuild. Had to change the radiator as it got a oval shape and started to leak, all the gaskets on the water pump blew earlier this summer and now that core plug popped out.
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