Rebuilding Bayliner - Volvo AQ125A - Head Gasket Question, Other Engine Questions

[Nickypoo]

Hello everyone, this is my first post here.

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Sorry if this is a little long winded, I tend to explain more than I need to. I will try to keep it as concise as I can.

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Here is a little intro to my situation:

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My dad and I are basically completely rebuilding a 1984 Bayliner Capri, Model 1950, Volvo AQ125A (Volvo 2.1L w/ closed cooling system). It was our neighbor's boat and he bought it new in 1983 and used it for like 2 seasons, and it has basically been sitting ever since. It even still has the '84 boat registration and trailer plate stickers on it. The problem is he had it sitting in his driveway without any kind of tarp or cover on it, so everything is rotted out or corroded :facepalm:. He did give it to us for free so we have that going for us.

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The rotted structure is another story and doesn't pertain to the category I'm posting in, so I'm not going into all that. We do have pretty much everything gutted from the fiberglass shell though.

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My engine questions start here:

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The engine is in ok condition considering its age. The bearings look good, and besides a little (carbon?) buildup on top of the pistons, the cylinders look excellent. I guess this shouldn't be surprising since he only used it a couple of seasons.

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The (aluminum) head is another story. While the bearings and camshaft are great, the valves are rusted and the rear exhaust port had kind of a fillet corrosion around the entire edge, so the edge was gone and it had been rounded out.

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So we decided to have the local cylinder head shop completely redo the head. They are called "American Cylinder Head Exchange", and I believe they are a national supplier. We dropped it off a week ago with the impression that they would fix it and call us when it was done. They said it would be about a week. I called today only for them to tell me that they disassembled the head and needed us to drop off a deposit. They could have called us or disclosed that when we dropped it off, but whatever. I went in to drop off the deposit and he gave me a very rough estimate of $550, not including the 3 valves that needed to be replaced. I payed a deposit of half the estimate, so hopefully that will light a fire under them.

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So my questions are:

1. Is $550 a reasonable figure for a complete reconditioning of one 4 cylinder head? (Including the exhaust port repair)
2. What kind of head gasket can I use? Can I get away with an automotive gasket since it has a closed cooling system and will run coolant? This will be run in salt water but if it has a closed cooling system I don't see why it would matter. (I already bought the headgasket set so I'm hoping this is ok)
3. What other miscellaneous issues should we watch out for?

Thank you in advance

 

[captmello]

Re: Rebuilding Bayliner - Volvo AQ125A - Head Gasket Question, Other Engine Questions

Welcome!

Sounds like a big project you've got on your hands.

Yes auto head gasket is fine. pick up an auto timing belt and tentioner while your at it.

 

[Nickypoo]

Re: Rebuilding Bayliner - Volvo AQ125A - Head Gasket Question, Other Engine Questions

Thank you captmello, that was what I was hoping to hear. And yes I have picked up a Goodyear timing kit for it as well.

 

[Nickypoo]

Re: Rebuilding Bayliner - Volvo AQ125A - Head Gasket Question, Other Engine Questions

Here's what the engine is looking like if anyone is interested. The first is when I first started dismantling it and the second is the most recent.



We are powdercoating everything we can with a powdercoating setup we got from Harbor Freight. The alternator, pulleys, brackets, bolts, and timing/impeller cover (white piece) in this picture are all powdercoated. The finish is way more durable than spray paint. I would recommend it for anyone restoring their boat if they can accommodate the equipment.

 

[captmello]

Re: Rebuilding Bayliner - Volvo AQ125A - Head Gasket Question, Other Engine Questions

Lookin' good!

 

[Nickypoo]

Re: Rebuilding Bayliner - Volvo AQ125A - Head Gasket Question, Other Engine Questions

Thank you captmello

We decided to replace the rings since now would be the time to do it. We aren't looking to spend too much money on the engine so we are hoping we can get by on just a re-ring. Does this look like normal bearing wear?



I'm planning on just using the old bearings. To my knowledge and from what I've read the bearings look good.

But I sure am glad we decided to go ahead with the rings. The first piston I pulled out had a stuck ring.

 

[Allbutwet]

Re: Rebuilding Bayliner - Volvo AQ125A - Head Gasket Question, Other Engine Questions

I would not reuse that. Replace the bearings at the very least. The only true test to wear. Is to Mic everything and check the wear against the wear limits for your engine. And the price for reconditioning your head seams awfull steep. It is always a good idea to get more than one quote. The powder coat looks nice. You should also Mic your cylinders before you re-ring the pistons. And hone the cylinders so your new rings seat properly. PS: You should start a resto thread if you haven't already.

 

[Rickf]

Re: Rebuilding Bayliner - Volvo AQ125A - Head Gasket Question, Other Engine Questions

Having just 2 yrs ago gone through the same problem on my 2nd Aq125 the 500 price tag back then is reasonable /if they are putting in the new cushions in the valve train, some valves, and adjusting them. pay attention to the valves, look for a etched looking circle on the back of the valves as I had 2 break in my other Aq125 the along the etching (18yrs ago don't remember intake or exhaust). the auto intake gasket is different , it is usable but there is a back port that you have to rework the gasket for or it will leak. Still have that engine for a spare. Having said that the reason I have the spare engine is my pretty hull and interior had a rotted floor and transom, transoms are repairable so is the floor if you have a LOT of time, patience and some money, interior is very expensive to repair. Do a cost analysis before you spend any more money as you will never recoupe a fraction of what you have spent. and to top it off you MUST run premium gas. maybe parts it out take the money and buy a newer boat, or find a good hull which is what I did and only had to redo the transom. Good luck, hope this helps

 

[Nickypoo]

Re: Rebuilding Bayliner - Volvo AQ125A - Head Gasket Question, Other Engine Questions

Allbutwet:

I suppose I should go ahead and replace the bearings then. I didn't really know since I'm not too experienced with engine internals.

I thought the cost of rebuilding the head seemed a little high too. But I guess they are doing a thorough job, and I think these Volvo heads are hard to come by. It's a little too late now to shop around since they have started the process already and should be done this week. This particular cylinder head place stocks rebuilt heads from almost all the manufacturers that you can just swap out your old one for. They don't stock anything Volvo. That tells me that maybe this is somewhat of a specialty. Edit: Also they are welding one of the exhaust ports to fix corrosion.

Thank you about the powdercoat, I think it's turning out pretty nice too. I was surprised how easy it is to powdercoat.

I got a free rental through O'Reilly Auto parts and got a ridge reamer and cylinder hone, although I'm having issues with the ridge reamer so I'm kind of hung up on that. I'm having trouble getting it centered in the cylinder so I haven't started the process yet.

Thank you for the suggestion, I'll start a resto thread as soon as possible. I'm still getting accustomed to the community here.​

Rickf:

I'm not sure what you mean by etching on the valves but when I pick up the head I'll ask about that. I know they are replacing three valves so maybe they caught the etching. I trust their work since they are one of the biggest cylinder head rebuilders in the area.

About the intake gasket, I noticed that too. Are you talking about the two holes on either end? I was about to order a gasket set from O'Reilly when I noticed in the picture that the gasket was different. I ended up ordering another set from somewhere else and it's the correct shape.

I am aware of the pitfalls of rebuilding the interior. The hull is sound. There's no turning back for us now; we've already received the shipment of 16 cubic feet of expanding foam, 7.5 gallons of epoxy resin, and of course the corresponding amount of fiberglass cloth. First thing we're working on this week are the stringers. I'm cutting them open tomorrow and getting the wood. I'll go into this in more detail when I open my resto thread.​

Thanks for the help everyone

 

[Allbutwet]

Re: Rebuilding Bayliner - Volvo AQ125A - Head Gasket Question, Other Engine Questions

Unless you actually have a ridge. Take the ridge reamer back. If you do Have a ridge then it is probably time for a bore. Otherwise hone your cylinders. Alot of novices have ruined a block from over reaming. This is something you should get help with from someone who has experience. But again if there is no ridge then just hone.

 

[Nickypoo]

Re: Rebuilding Bayliner - Volvo AQ125A - Head Gasket Question, Other Engine Questions

There is a very very slight ridge. Nowhere near enough to catch a fingernail on but I can feel it by running my finger across it. I don't want to hone the cylinders without taking them down because the honing stones won't sit perfectly flat against the cylinder wall when I run the hone across the ridge.

I agree it would be best to have someone more experienced help. But I am very cautious and work slowly. I am not very experienced with engine internals but I am otherwise very mechanically inclined.

I'm about to go mess with it right now. I have an old one cylinder industrial engine block sitting around here that I think I will practice on first. Of course if things aren't looking/feeling right I won't proceed with the reamer.

 

[Nickypoo]

Re: Rebuilding Bayliner - Volvo AQ125A - Head Gasket Question, Other Engine Questions

Well the results are in... and it passed my fing-ometer test.

I only had time to do one cylinder because I was checking, double checking, triple checking, and so on and so on. I first reamed the ridge which almost took it completely away. There was still barely a slight ripple when I slid my finger across it. I then honed it and now there is no discernible anomaly in the surface. Looking from the bottom up with the old one-eye check, the cylinder looks completely straight.

I don't really like my honing pattern but I don't think that makes a difference in function.

 

[Nhpatriot]

Re: Rebuilding Bayliner - Volvo AQ125A - Head Gasket Question, Other Engine Questions

Nicky...
I have the same engine (and same boat too). I just discovered a problem with the rear most exhaust port.
I'm trying to determine if it's a manufacturing mistake or deterioration over time.
Do you have any hint of this on your head?

 

[Nickypoo]

Re: Rebuilding Bayliner - Volvo AQ125A - Head Gasket Question, Other Engine Questions

Nicky...
I have the same engine (and same boat too). I just discovered a problem with the rear most exhaust port.
I'm trying to determine if it's a manufacturing mistake or deterioration over time.
Do you have any hint of this on your head?

Hi Nhpatriot, yes I had the exact same thing on my exhaust port. Yours is much further along than mine was though. It's corrosion over time. It's very common on these engines. You're probably going to need to take it to a machine shop and get it welded back up like I did.

 

[Nickypoo]

Re: Rebuilding Bayliner - Volvo AQ125A - Head Gasket Question, Other Engine Questions

Also I got this engine put together and running on a stand. I posted a video in my resto thread: http://forums.iboats.com/showthread.php?t=555694

 

[Nhpatriot]

Re: Rebuilding Bayliner - Volvo AQ125A - Head Gasket Question, Other Engine Questions

Thanks for the info. I wonder if it was worsened by the rubber flap check valve on the exhaust outlet by the prop disappearing a couple years ago.
I'm going to see if someone can tig it while still in the boat and then I'll grind it smooth. Only need a little more meat for the gasket to seat against, it doesn't have to be as thick as original equipment.
Just trying to get couple more years out of it before I upgrade.