CAT 3516 problems

I am curious if any engineers on here work with 3516’s and if so are you having trouble with dropped valves, and excessive valve recession. The vessel I work on has high displacement 3516B’s for mains and we are experiencing a lot of valve issues, mostly with the intake valves. We are doing valve lash adjustments every 1000hrs just to stay ahead of the wear. I would be very interested to hear from anyone who has seen similar problems. <br><br>Thanks,

I am assuming you are replacing valves,seats and checking all the normal stuff. If so who is supplying the parts? Is Caterpillar doing so? If they are you should contact them. They are going to tell you to check your intake air for proper filtration and want you to check normal stuff like gov. settings, fuel air ratio control etc, tell them you prefer they do those tests and provide results in writing. If the problem persists tell them you are wondering about the quality of the metal in the seats and valves. Tell them you are considering sending samples to an independent metallurgical testing facility for tests. <br>Engine manufacturers subcontract a lot of their fabrication of parts and sometimes the quality control at the subcontractors is sub par but most engine manufacturers appreciate their attention being called to a recurring problem. Give Cat headquarters in Illinois a call if the problem continues.<br>Good luck.

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Correction to dirwood,<br> Talked to the best 3516 guy I know after he appeared on my patio looking for a steak. We are both only accustomed to the 3516 being used as an auxiliary generator but it’s still a Cat. Problem is probably not the seats and you probably do not have the means to machine them anyway. As usual you need to think 1. what has changed? [load swing or increase etc] 2. when did the problem appear? 3. do they correlate? It’s a step by step process as I am sure you know. We both agree everything else I said before stands.<br>Best of luck.<br>.

<P>Our gen sets are 3512’s. Different application as they are constant speed with load sharing. We have had no top end failures.<br><br>My first question was Cat or after-market parts? Has lube samples indicated anything? Lube compatibility? Fuel quality? After cooler? Shutdown damper fully reset? Happening on both banks? Injector trim codes properly entered?<br><br>Also, with the smoke mapping program on the 3600 series, I have run across critical RPM ranges where turbo inlet/outlet temps go through the roof. <br><br>Electronic diesel engines…My old Chief is flopping in his grave! Give us more info and good luck!</P>

<img alt="" src=“” _height=“75” _width="75]<br><br>This picture is of intake valves from the same head, they had 8000hrs on them. Note the difference in wear.<br><br>All parts are CAT, no after market stuff. After inspecting the heads removed during the first top end it was found that all the upper intake valves were recessed .030-.065. Both exhaust valves and the lower intake measured the same, showing normal wear. Now with only 4000-5000 hrs on the new heads we are seeing excessive recession, again only on the upper intake valves. Oil samples done by CAT SOS labs all come back good. We are using Chevron DELO 15w-40 for lube oil.

What does Caterpillar say when given this information?

<P>CAT claims it is with in tolerance and normal for the hours/fuel used. I find that hard to believe. I recently spoke with a couple CAT service technicians and they both said they have noticed they are making a lot more intake valve lash adjustments when performing tune ups for customers than they did with the older engines. </P>

Send a letter either FedEx or registered mail with delivery confirmation requested to Caterpillar in Peoria Ill. detailing all the information you have and the problems experienced. I have used the address for Investor Relations for things of this nature, that usually results in it getting properly routed. Tell them you are concerned for Caterpillar’s reputation. Include in your letter problems including loss of money caused by down time and ask them if they have decreased the quality of the material in their valves recently or changed suppliers. Offer to send them an old valve that had 8000 hrs on it and a more recent one that only lasted 4000 hrs so they can have a laboratory examine them. <br>See what they say. Believe me they will respond. Let us know how things turn out.

Sounds like a good game plan with Wartsila cutting into Cat’s high speed engine market.<br><br>I haven’t seen this much wear on our gen sets. The only problems I’ve had are engine driven pumps, dampers, and the odd injector. <br><br>The biggest complaint I’ve had with Cat was in the transition and modifacation of the 3600s to the full electronic version. We’re still having a hard time getting the latest parts and parts manuals.<br><br>I’m still curious how the warranties will play out with the “fuel burned” being the measurement.

Injunear,<br>Wartsila is currently a better engine among the medium speed engines in my opinion [though the cooling system is over complicated]. I know Cat has had problems with parts manufacturers and will correct the problem if it’s brought to their attention. Who knows? Maybe they asked ISO certified Moo Goo Gai Pan metal manufacturing over in China to make valves for them. ISO certification means little now a days. I see this stuff all the time.

HI all Cat engine users, I’m Johnny Pettersson and i work as a Gearbox expert resently from Vestas Wind SV AB.
You are taking about a problem with the Cat 3516 engine that i feel we can have a problem solution for.
1:st There is a problem with the oil, how many hours are you runnung the oil?
2:nd How fine is the filtration of the oil ?
3:rd If there comes to a repair ,there is a company in sweden that specialise on plasma welding marine diesel engine valves and refurnice these to a new valve with a much stronger surfice.
( I don’t know at this time how big these valves are and if there is a economy saving to repair the valves)
however ther is a solution to the oil problem…
It’s called Europafilter and you can read about at
They have achived some miracles on the market with both filtrations of the oil and ofcause filtration of the fuel.
The filter system cleans down to 0.1 microns and it removes 98,3 % of all water content in the oil / fuel.

I’m always avalible for a conversation at my E-mail

I worked as a Cat mechanic back in the 90’s and we had some engines that were doing the same thing… except it was exhaust valves that were “growing” we kept having to adjust the valves… and then change the heads way ahead of normal conditions… We finally found that the engine was overloaded by about 15% above factory guidlines. Have you added equipment to the vessel? New props? Check exhaust temperatures? What are they at full load, speed? How about stack condition? any smoke? if so what color?

Pull a valve cover off, start and run the engine from cold. It could take as long as 20 minutes to get oil up to the rocker arms. This seems to be normal in the 3500 series.
If you observe this don’t put any load or RPMs on her till it’s fully warmed up.

In our case, block heater, oil heater and pre-lube pump (all aftermarket) did nothing to improve this condition because of the small passages involved in the valve train, the old path of least resistance thing.

I’m sure you’ve checked valve guide dimensions and seals.

I have a question about the recession on a 3516wpw it is a natural gas motor but im sure they are just about the same. when i zero my tool out and then check the valves, whats a good number to see and whats a bad number?

From 3608 ressession on this was -900


Is that picture you posted of intake or exhaust valves? Are you asking for valve lash numbers or valve recession measurements?

I know a guy that has a pair of them in his rig in Alaska and had a lot of trouble with them. When one finally let go they figuared out what happened. It droped a valve and when they took the head off it was discovered that there were no valve seats installed at least in the cylnder that let lose. From what I understand the valve seats are an insert on that engine.
He had rotton service from the alaskan dealer. He had spent a lot of money in trying to figuare things out prior to it blowing up, plane, housing, $ 125.00 per hour.
He had to fly a guy out from Anchorage It was past warrenty, very low hours. We only use the boats about five weeks a year and maybe 500 hours a season.He could’nt have more than 600 hr on it. NC replaced the engine when they determined what went wrong.
I beleve both engines are for sale, he is re-powering with John Deere

The problem is they say CAT on the engine. We have had nothing but problems with our CAT’s in all our new vessel. We have CAT 3608 C280 in my boat and I’m currently on my third engine on the port side. You have read correct engine #3 on the port side. The first on failed with just 109 hrs on the clock during sea trials. The second one failed last week @ 6248 hrs slinging a rod out the block on cyclinder #2. Tore the wrist pin out from the piston, rod bolts broke, and one exhuast valve dropped. these engines are used in CPP system @ 1000 rom. L/O is change every 1000 hrs and filter are changed every 500 hrs. We also clean the lube oil centrifuges every 250 hrs. Never ever had this problem with EMD engines.
We have car Accert C32 for generators. Basically 3412 engine driving 900 KW generators. That is the biggest POS on the market. Get ready to change a thermostat housing or water pump every 500 hrs with you 500 hr L/O and filter service. Why the hell would you ever put an aluminum housing on a engine? CAT still warranties the generators because it’s a nation wide problem with these engine eating up thermostat housings and water pumps.
As far as the 3516/3512 engines. I’ve worked with old and new and haf nothing but problems with them. Main cause is dropping valves, to bad injectors during start up and blowing right out the valve cover, and spinning bearings. Personally the best cat engine I worked with is the old school 398/399 engines. These small engines they are getting all this horsepower just wont last. Reminds me of the old 149TI DD, the put out alot of hp and never lasted long. Basically a throw away engine.
When it comes to raw torque your not going to beat a EMD, GE, or Alco. People can say the 3600 series is up there with those three, but I take it off the list for the reliability issues. That’s just my opion. For what it’s worth. I got in a nice talk with the CAT guy about these engines. And was told comparing CAT to these engine is basically apples to bannas. He said CAT is the best engine on the market. when I asked about the reliability issues, he told me CAT like to push the engines, that’s why there’s problems. Makes alot of sense to me to have a high hp engine that can’t take you to far without breaking.
I attached some pictures of the recent failure with the 3608 C260.

You need to be more forward thinking. That old school “keep the parts inside the engine” way of doing things isn’t the rage.

I heard that if you paint these engines grey that they will think they aren’t Cats anymore and will run a little better. DD green works, too.

What are you talking about? CAT’s are great engines!

…right up until they blow-up.

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